This is very similar to a question that was posted earlier - so I will provide the same information for you.
You are describing what Social Security refers to as a "Representative Payee." A representative payee is assigned when Soc. Sec. feels that you need assistance with handling your money. A Global Assessment of Functioning Score of 50 indicates a serious impairment in social, educational or occupational functioning. While a low Global Assessment of Functioning Score can often be useful in obtaining an award, it may also cause the ALJ to name a payee. Usually, Social Security will name someone that you / someone who is helping you as your payee.
You have 60 days to appeal the decision to use a payee. I will assume that you were represented by an attorney. If so, you should contact him/her as soon as possible to discuss this issue. Remember - you have a limited time to appeal the decision.
I hope this works out for you - best wishes
You do have the right to appeal but in my experience this type of appeal is not successful. Typically the issue of a representative payee arises where there is a mental impairment and a GAF score of 50 does indeed indicate that type of impairment. The appointment of a representative payee is independent of whether or not you have ever been determined to be incompetent by any Court.
This information is provided as a public service to provide a general answer and should not be relied upon as legal advice.