New to Apartments, someone parked in my assigned space???

Hi. I been in my new place for almost a week. I have been the only one in my assigned parking spot until yesturday. I came home in the morning, and a car was in my spot. So I left the house and another car was parked there, but it looked like they were just waiting on someone. So I come home a little later that evening and that same car that was parked there overnight was there again! The office gave me a number for a towing company when i first moved in. Should I write them a note and put it on their car first or just call the towing company? What should the note say? I don't want to be rude and say hey, don't park here no more... any suggestions?

Maybe it was an accident, the person parked there didn't realise?

If you don't know exactly who parked there, pop a polite note under their windscreen wiper saying that you're sure they are unaware of the fact that you have moved in recently and been allocated that parking space. I wouldn't involve the towing company right away, you don't want to make an enemy after one week!

Put a note under the windshield that says You have parked in a reserved space and I have the right to have your car towed. I don't want to do that. Please park elsewhere." If they are still there in 24 hours, tow them

have it towed at Owners expence or at least report it to the manager of the property

If there's a sign warning people that unauthorized parking will result in towing, call the towing company. The sign takes the place of your note. Don't worry about being rude.