When I try to enter my email address, I get the error it's already in use.
Well, I'm 100% sure it's my email so it's seems someone is using mine in OSM. Can it be transferred to me?
Send a mail to firstname.lastname@example.org with a clear explanation of the problem and also include your manager name in the mail.
"It's fine to celebrate success but it is more important to heed the lessons of failure." -- Bill Gates