rear trunk door

Your car is luxury all the way. You no doubt have a power liftgate. Usually what goes wrong with them is caused by the sensor which will stop the door from closing if there is something in the way or a drag on the system. Sometimes all that is necessary to fix this problem is to lubricate the pistons. Try greasing the hatch struts with silicone grease (same grease used for spark plug wires), where the stainless steel tube comes out. Put a thin film on the weather stripping too. Any drag on the system can throw the safety sensor and cause the liftgate to malfunction. Of course, if you have broken anything, you will have to replace the broken part.

thanks Gregory!!! I already checked and the right tailgate lift support is broken. I have to replace both, when I was about to buy it ,,, it asked me if I want it powered or without???

reading again your answer, I understood that I have to buy the powered lift support. Thanks again for your help. I will let you know when everything is fixed.