In WI, if a tenant cashes the return check for their security deposit can they sue for more?

I had some lets say not so great tenants. They left the apartment in bad condition.
Within the states allowed time, I sent them a letter stating the amount of their refund, and a detailed list of repairs/costs.
It was nowhere stated as a offer amount, and the tenants cashed the check. Now, two weeks later, they are calling and complaining about the charges. Do they have any legal right to dispute?