Legal Question in Landlord & Tenant Law in Washington

Yes there are. RCW 59.18 (you can google this) is the state Residential Landlord Tenant Act, and it spells out your rights in this situation. That said, most of the time, when folks post something like what you posted, there is a lot more to the story than meets the eye. If you have never been late on the rent, and the landlord claims you were late on the one time you can prove by time and date stamped receipt that you were not late, it seems to me that there is more to the story.

I can only help you in so far as you provide enough information.