was the EITC claimed on the original return? if so, the refund should have included the adjustment for it. if not you'll need to file an amended return.
https://turbotax.intuit.com/tax-tips/amend-return/how-to-file-an-amended-return-with-the-irs/L6kO691...
you'll need to include the EIC schedule with the return.
make sure that line 8 on the 1040 reflects the UC exclusion
and that the refund already received is reflected on line 18 of 1040-x
other lines may change because of the reduction in adjusted gross income
expect this process to take 4 months or more.
