Parking and Access: Can a Leasing Office Tow a Tenant from an Apartment Parking Lot

My question involves a possible towing situation in the state of: Pennsylvania. I am a tenet of an apartment complex. if I park my car outside of my apartment along the street I have 1st floor access. if I park my car in the lot of the complex I have 2nd floor access. I decided today that I wanted to walk up the stairs today. I parked in the lot. The leasing office stuck a tow away sticker on my car stating I was parked in a reserved spot, ie: my car was not allowed to be parked there in that lot, also that my registration for the car was out of date. this is the only lot that would be reasonable to park in for my apartment. As of January 1st 2017 in the state of PA registration stickers are no longer issued. the apartment complex does not have reserved spots for the tenets as well as we do not have parking permits or anything. my car is registered, up to date on said registration and is listed on my lease. I pay my rent, I have every right to park there. I plan on parking there in the future. can they tow my car? and if they do tow it what rights do I have?

Thanks for your time,

Ericalg

Parking and Access: Can a Leasing Office Tow a Tenant from an Apartment Parking Lot