Monterey Apartments They put a false and blame, sent a notice to pay 600 dollars and vacate the house in 5 days Waukesha, Wisconsin

We moved to Monterey apartment on 30th August late and found huge number of Bed Bugs in Bed Rooms and Bath Rooms. On the first day itself we had called the Monterey apartments to complain about the bed bugs. Bed bug treatment was done three times in a month in our rented apartment and before doing the treatment they didn't tell us how much they would charge us. Suddenly we got a notice asking us to pay 600 dollars for the treatment and they had put a false blame on us that we got the bed bugs in the apartment. Please help us to solve this problem and get out deposit amount 500 dollars.