Register an account in your own name
Make the account at Special:CreateAccount before anything else, and make it a person, not a brand. Wikipedia's username policy classes a name that's only a company, organization, website or product as a promotional username, and it doesn't permit shared accounts: any user account should represent an individual and not a group. An agency logging in as the client's name is a problem before the first request goes out.
One human, one account, and you keep it. Everything you file is public and permanently attached to it, and a reviewer will look at that history before acting on what you send. Opening a second account after a decline doesn't work and puts the first one at risk, so register the account you're going to use for every request you ever send.
Disclose before you write a word
If money is involved in any form, employee, contractor, agency or freelancer, disclosure is mandatory under section 4 of the Wikimedia Terms of Use: you must disclose each and any employer, client, intended beneficiary and affiliation with respect to any contribution for which you receive, or expect to receive, compensation. The Terms accept a statement on your user page, on the talk page, or in the edit summary. English Wikipedia practice is to do the user page and the talk page both, so do both.
On your user page, put {{paid|employer=name of employer|client=name of client}}. At the top of the article's Talk page, put {{Connected contributor (paid)|User1=Username|U1-employer=Name|U1-client=Name}}. That pair gets swapped constantly, and a disclosure sitting in the wrong place reads to a reviewer as no disclosure at all.
If nobody's paying you and you're the subject, a relative, an officer or a close associate, the Terms of Use clause doesn't bite, but the conflict of interest guideline still expects the disclosure. Put {{Connected contributor|User1=Your username|U1-declared=yes}} at the top of the article's Talk page, and state the connection in the edit summary of anything you post. Optional on your user page: {{UserboxCOI|1=Wikipedia article name}}.
Write the change out first
Write a replacement, not a complaint. Wikipedia's edit request page gives the format outright: Change X to Y; Insert X after/before Y; Remove X. Quote the sentence that's wrong exactly as it stands in the article, then give the exact sentence you want in its place. A request that describes the problem instead of naming the replacement gets declined with the reason The request was not specific enough.
Every addition needs a reliable, independent, published source, and every removal needs the sources that contradict what's on the page. Your own website, your press release and your company bio are none of those. Split a large correction into several small requests, because a volunteer will act on one discrete checkable change and stall on a bundled rewrite.
Draft it by hand. The instruction is blunt: Do not use AI or LLM tools (such as ChatGPT, Claude, Copilot, etc.) to write any part of your request. There's a decline code for a change that appears to be AI generated. Promotional wording draws a decline on tone alone, even when the fact underneath is right, so cut the adjectives and write it the way the rest of the article reads.
Post it on the article's Talk page
Open the article and click the Talk tab at the top, sitting next to Article. On the talk page, click the Add topic button (Wikipedia's own written instructions still call it New section, so look for either). Put a plain title in the Subject field, Edit request is fine, and don't argue the case in the heading.
In the body, put {{edit COI}} on the first line by itself, then your request underneath, then ~~~~ at the end to sign. Those four tildes are what timestamps the request and queues it, so a request without them isn't properly filed. Use {{edit COI|N}} if this is your first request, {{edit COI|R}} for a substantial rewrite, and {{edit COI|summary=Short summary of requested change here}} to hand reviewers the one-line version.
Preview it, confirm the template rendered as a box rather than as raw text, then save. In the Add topic tool the save button is also labeled Add topic; if you land on the older form instead, the buttons are Show preview and Publish changes. Don't set the answer parameters yourself. A, G, U, P and D belong to the reviewer, and marking your own request answered takes it off the list of open ones.
The no-editing rule is a guideline, not an absolute. The conflict of interest guideline says you are strongly discouraged from editing the article directly, and it names the edits you may still make yourself: remove spam and unambiguous vandalism, remove unambiguous violations of the biography of living persons policy, fix spelling, grammatical, or markup errors, repair broken links, remove their own COI edits, and add independent reliable sources when another editor has requested them. If another editor objects for any reason, it is not an uncontroversial edit. An unsourced defamatory line about a living person is the one thing you never queue for six months: take it out, say plainly why in the edit summary, and raise it at the biographies noticeboard.
What happens next, and what the codes mean
Then you wait, and there's no queue position to check. Wikipedia states it plainly: it can take anywhere from a day to several months for an edit request to be acted upon. No service level, no expedite, nobody to call. Don't edit the article while you wait, beyond the uncontroversial exceptions above, because doing it yourself is the thing the whole process exists to avoid.
A volunteer with no connection to the subject reviews it and marks the result: A accepted, P partially done, U under review, D declined, or G, which means you may go ahead and make the change yourself. G is the only clean permission to touch the article text, and it covers that one request, not the article generally.
A decline carries a reason, and the reason is the instruction: ADV for promotional tone, V for changes not supported by neutral independent reliable sources, O for an omission that unbalances the article, R for removing well-sourced content, S for a request that wasn't specific enough, T for a change that wouldn't improve the article. Fix that exact thing and file once more with better sourcing. Refiling the same request unchanged reads as tendentious and puts a topic ban on the table.
Don't go looking for a corrections desk while you wait, because there isn't one. Wikipedia's own page for article subjects says it in one line: Wikipedia articles are maintained by volunteer editors; there is no centralised review system. It gives no email address for getting an article fixed and routes you back to the Talk page and the same template.
If it's still wrong after six months
Six months of silence is a decline, in the words of the instructions: if nobody responds to your request even after six months, treat it the same as a declined request. Everything after that is on-wiki and public, so decide what you're willing to have discussed in the open before you escalate.
If the article is about a living person, the biographies noticeboard is the strongest lever you have. Post at the BLP noticeboard and follow its instruction exactly: do not copy and paste defamatory material here; instead, link to a diff showing the problem. Contentious material about a living person that's unsourced or poorly sourced is supposed to be removed immediately, which is why that board moves when an ordinary request doesn't.
For procedural help, the Teahouse has an Ask a question button and answers new editors who can't work out why a request stalled. Know what the conflict of interest noticeboard is before you go near it: it exists to determine whether a specific editor has a conflict of interest, so it's also where an agency pushing too hard gets reported.
What this doesn't fix
If the independent published sources say the unflattering thing, no procedure on Wikipedia changes the article. It reports what those sources report, and a request to take out well-sourced content gets declined under the code for exactly that. The work that moves the article is the work that changes the source record first, and that's a different job in a different place.
This is the route for an article that already exists. If there's no article yet, that's Articles for creation and a different process, and you can't review your own submission there or anywhere else. It's also English Wikipedia only: other language editions set their own paid-disclosure policies under the same Terms of Use, so a German or French article is its own project with its own rules.
Nobody sells access. There's no paid tier, no expedite and no relationship that moves a request up the list. What you can buy is somebody who does the sourcing, writes the request so a volunteer can act on it in one pass, and files the disclosure correctly the first time. That changes the outcome. It doesn't change the queue.