You can find the entire list of acceptable documents for proof of social security here:
https://sumtertaxcollector.com/driv.html
Typically, this is a Social Security Card, 1099, W-2, or Paystub. The item must display your full name and Social Security Number.
If you do not have any of those documents, you can call the tax collector’s office and ask them the best thing to do. You can find the phone number of each location in Sumter county here: