If you are unfamiliar with wiki-editing, take a look at Help:How to edit a page. It is a concise list of technical guidelines to the wiki format we use here: how to, for example, make text boldfaced or create hyperlinks. Feel free to practice in the sandbox. If you would like a slower introduction we have a short tutorial.
These links may help you familiarize yourself with Wiktionary:
Entry layout (EL) is a detailed policy on Wiktionary's page formatting; all entries must conform to it. The easiest way to start off is to copy the contents of an existing same-language entry, and then adapt it to fit the entry you are creating.
Check out Language considerations to find out more about how to edit for a particular language.
Our Criteria for Inclusion (CFI) defines exactly which words can be added to Wiktionary; the most important part is that Wiktionary only accepts words that have been in somewhat widespread use over the course of at least a year, and citations that demonstrate usage can be asked for when there is doubt.
Look in the New signature: text box for your custom signature code. This contains the name of an account, but it's not your account. It's probably the name of another account that you used.
Change the wrong account name to your current account name.
If you have more than one account, and you are trying to link to the other account, then change at least one of the links to your current account name. For example, change [[User:Username|Username]] ([[User talk:Username|talk]]) to:
[[User:Username2|Username2]] ([[User talk:Username|talk]]) (one link to the current account's userpage, and one link to your other account's talk page), or to
[[User:Username|Username]] ([[User talk:Username|talk]] • [[Special:Contributions/Username2|contributions]]) (two links to your other account and one link to [[Special:Contributions]] for your current account).
Click the blue "Save" button at the bottom of the page. (The red "Restore all default settings" button will reset all of your preference settings, not just the signature.)
After you have done this, the error will be fixed. If the error is not fixed, then clicking the blue "Save" button at the bottom of the page will produce an error.
I thaught that after changing my username the redirects from my former name to a new one are created automatically and it isn't a problem. So, as you say it is, okay, I change it. Sic dixi REX CAERULUS21:52, 6 April 2021 (UTC)Reply