Are you trying to enter a SSA1099 and then did you click the wrong entry screen for it and choose the one for railroad retirement?
Go to Federal> Wages & Income>>Retirement Plans and Social Security(SSA1099 and 1099RRB) to enter your SSA1099.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
Did you enter any social security benefits on SSA-1099?
If you did, I suggest you return and check that entry. It sounds like you may have checked RRB-1099 (Railroad Retirement) instead of SSA-1099 (Social Security)
If that happened, be sure to delete the erroneous entry (RRB-1099) and then enter the SSA-1099.