Problem fitting a new door actuator

[hancoxk]

I was having trouble with the grinding noise when locking my car and was advised it was the door actuator, tried fitting the new door actuator I purchased to my nissan micra 04 today and once fitted the noise stopped but the door wouldnt close so as we were running out of time they put the old one back in and had the same problem,the door wouldnt close with the old one either. We managed to get it to close and lock and now it doesnt want to open so have to climb through the passenger side when getting in the car, just wondering if we missed something really simple in the installation or if you think the new door actuator may be faulty. Thanks for your help