Jagsp

Hi. I’ve just joined this community and hopefully someone may be able to help. I have a w208 cabriolet with roof issues. I have bought the vehicle with roof fault. It used to work apparently. It only worked once magically for me. The vehicle has had a star machine with no fault codes, the fluid was low and I have topped it up to the max line but still no good. I can see on the right bow cylinder slightly wet. You can hear the motor/pump whilst pressing button the bow unlocks then nothing happens after. I have attached the video. I was going to buy a 2nd hand pump but I don’t know if that will cure the problem?? Any help much appreciated. Thanks Ps I will have to upload some underway as file is too big. But you can hear the same noise as you would whilst pressing the headrest up and down.