we don't know your complete situation. If your w-2 should zero for box 12 code A you should not owe the fica taxes on uncollected tips.
you have to be careful on the w-2 there is box 12a, 12b, etc but in the box there's also a code letter.
Box 12d could show code A.
that number does not appear by magic. only you make entries for your return. So why $6963 would show up in your efiled return is unknown.
Check your w-2 transcript with the IRS or call them
https://sa.www4.irs.gov/secureaccess/ui/?TYPE=33554433&REALMOID=06-0006b18e-628e-1187-a229-7c2b0ad00...
if it doesn't show the amount and you got a notice from the iRS about owing taxes due to that entry follow the instructions for disputing the bill. This would be best served by preparing an amended return without that amount and sending it with the notice. be sure to sign and date it and use a tracking service
