"For 2023 I contributed 7500 so the current cost basis reported should be 14500. "
that statement would be true if
"The prior year (2022) Form 8606 showed a basis of 7000. on Line 14 "
A correct 2023 Form 8606 would show a prior basis of all contributions up to and including 2022
and a contribution of 7500 on Line 1
The discrepancy is then ( $total contributions up to 2022 - $7,000 )
In other words your 2023 reported basis is changing from $7000 + $7500 to
$total contributions up through 2022 + $7500.
It seems simplest to file only a correct 2023, as I suggested earlier.
If IRS accepts the suggested explanation, they may not bother to look for any discrepancy on earlier forms.
@topmiller
