You knew the new rule that required a sticker.

You had a sticker and lost it.

You parked without a sticker.

You got towed.

I don't see where the owner did anything wrong.

The owner has no obligation to replace your lost sticker on your timetable.

Frankly, it should have been affixed to your vehicle the moment it was in hand. Without it your car could have been towed one minute after the sticker was provided if it wasn't on the car so what's the difference as to when you were towed?

If you don't agree you are welcome to sue the owner in small claims court and see if you can convince a judge that you are correct.