Sorry this is happening. What phone brand/model is it? Who is your carrier? Unless someone comes up with something else, unfortunately you ate going to have to Factory Reset the phone and set up from scratch. Hopefully you had some backup solution implemented, as Factory Reset will erase everything. You will always need know your Gmail account and password. If you don't know the password, and you have to reset it (Google 'Google Account Recovery') you could potentially be locked out for 72 hours (I can share a link for a workaround for this 72 Lockout)