Tenant does not want to pay Postage Fees

Hello all,

I am letting my tenant know that they owe me the $76 + postage fees + gas (for all the trouble I went through with Regie du Logement).

They told me that they only owe me $76 and not the postage fees nor the gas. They called the Regie and apparently they told them they are not obliged to pay for postage nor gas only the $76.
Does any have a direct link or reference to where it states the tenant has to pay for postage fees + gas as well?

Thank you!