HSA Return of Excess Contribution for W-2

[Guest Scrabblebug]

We have an employee that contributed to his HSA after he signed up for Medicare. We have requested the return of the excess contribution. When we receive the funds back, we will pay him and withhold the proper taxes. I don't know what I need to do in Box 12 of his W-2 since the contributions will show up there. All of this has or will be done in the same tax year.