Nissan,If I get my blower motor replaced, do I also have to have my Ac recharged after replacing blower motor?

Heat went out in the car. Took it to the dealership, they said it was the blower motor. Paid to have it replaced. Upon picking the car back up the heat worked, but my Ac does not. Ac was perfectly fine upon giving them the car. Is it normal to have to recharge a Ac after replacing that part? Or did they mess something up? Their claiming it has nothing to do with what they have had to mess with to replace blower.

My car has 117000 miles.
My car has an automatic transmission.