@Samuel_Paes , could you try updating to version n8n 1.23.0 or greater? There was an issue as a result of our infrastructure change that was fixed but requires an update.
I can’t be certain that it’s the same issue given the error here, but it would produce a 403 error. If you’re confident that you have access to this workspace and are on a version older than 1.23.0, then it could be the issue.