Terminating an employment unlimited contract due to salary deduction

Respected Lawyers,

My employer is deducting AED 3000 from my salary every month while my contract is not changed for the deduction. I have the following questions regarding this point:

1. Can I claim these AED 3000 from my employer via a labor case?

2. If I file a case in the labor against my employer, can my employer terminate/cancel my contract during the case or does he have to wait until my case is resolved?

3. What is the maximum time limit for a case to be resolved?

My contract is unlimited.

Thanks!