Right outside mirror!

Hello friends! I have a little problem with my V 40, BJ: 2003, MJ: 2004, 90 kw 122 hp, automatic AW/ 50-42, motor B4184S2. The right exterior mirror housing is a little loose in the anchoring in the door, compared to the left exterior mirror housing. To the functions: Both mirrors can be folded on to the doors, by hand. Both mirrors as well as the rear flap are heated bar. Via a joystick in the driver’s door I can change the position either the left or right mirror in the housing. But that all works. The case for the mirror is a little loose at the passenger’s door and would like to screw it down yourself. Can you please write me how to put it on?