If something goes wrong creating your listing, it’ll show the problematic error that caused it and it won’t be posted.

Check the error and see if its something fixable, you may have to adjust some content of your listing before re-posting it, such as an invalid input may contain invalid characters.

If the error is something not related to inputs such as API not available then the server might be down, if the problem is not fixable then please contact support or try again later.