Answered on May 08th, 2013 at 10:21 PM
Rule #1 - everything SSA sends you is important. Keep it in a safe place with all other items from SSA, preferably in a water-proof container in a secure place in your home, or where you know it will be safe. SSA does not keep a copy of the letters that they send to you.
Rule #2 - document who, when, how and where you speak to SSA about this issue, and any other.
For this problem, send a letter to the local SSA office https://secure.ssa.gov/ICON/main.jsp setting out the problem as you have done here. In the final paragraph, demand that a new assessment of your backpay be completed and that you be notified in writing. Hand deliver the letter and get a paper receipt or copy of the letter with a notation from the official that received in the event you have to prove later that you hand delivered it.
If the decision is that they owe you no money, and the reasoning or logic or facts are not correct, appeal.
No attorney-client relationship has been established because of the information provided. Seek local counsel to address your particular facts. MJHJ