My rent check was returned for "uncollected funds". My landlord now wants me to pay a fee of $35.00 for each check that was returned by THEIR bank. When I read the lease, it looks like I only owe a $35.00 fee for my check. The lease states:

LATE FEE COSTS AND RETURNED CHECKS: If any installment of rent is not received by the landlord within five(5) days from the due date, Tenant covenants and agrees to pay as additional rent, the sum of fifty dollars. Tenant further agrees to pay a handling charge of $35.00 for each check returned by the bank for insufficient funds or any other reason. Returned checks will not be redeposited. In case of a bounced check, Landlord may require any and all further payments to be made by money order or certified funds.

Which is it and how should I resolve this?