Anon, I can give you some information to help
as I have had the exact same experience.
When you try to get into this "system" they will require a great deal of information from you.
5 years previous work history, copies of every single Doc, hospital, xray, scans etc - all of your medical records and much more.
Without an attorney, you will struggle getting everything needed and take many years trying to figure it out.
The good news? They have to go back to the original file date when YOU WIN.
Get an attorney.
God Bless You Anon.