Customer withholding final payment when damaged two pocket doors we’re on a separate contract can we do that

Can my customer hold back a $6700 check for a contract that I finish the tile floor and demo but on a separate verbal contracts are damaged and scratched on the door so they’re withholding my $6700 until the damage is fixed the scratch All the work in the contract has been completed on the verbal second contract we did indeed scratch the door where the nail that hit another nail and scratch the pocket door solitary I’m not denying responsibility but that’s on a separate invoice what do I do