Playing armrests :(

Merhabalr friends. I have a 2003 model 307. I have noticed that the front seat armrest is a little too shaky nowadays. I looked a little but I couldn't see a screw to tighten. Is there any way to reduce shaking? By the way, I can't rest the arm, it's not later on :)

Is this factory outlet? or is it stuck later? then the plastic may break. If it is original, you can squeeze it in the service, if you have a hand, you can tamper with it. Take a good look to the left. When playing with your hand, you will find where the sound is coming from.