Start here:

https://www.irs.gov/businesses/small-businesses-self-employed/correcting-employment-taxes

There are two ways to handle this. One is that the Gross Payroll is Draw, which means all of the refunds go back to this owner when the business gets the refund checks. The other way is to treat the employer share of taxes as refunded against the expense entries, and only the employee share is returned (which means Gross Wages is changed to draw).

The point is to no longer have anything as expense, because it isn't expense, for purposes of this category.

This is fairly generic advice, of course, and overlooking nuance, such as FEIN, insurance, State, and other mistaken issues for not being an S Corp. And overlooking whether that even is advised.