Transfer of job with or without company permission.

I am working in ksa in food company i m from india company has brought me here in labour visa but my profession is driver company told they will give me driver job and driver salary but here i am doing job as a driver but they are not giving me driver salary what i should i do they are taking advantage of my giving labour salary and telling me work as a driver.
So plz help me out from this situation what sholud i do now i want to change company with or without my employer permission.
If they allow what is the procedure.plz tell.
If they not allow what is the procedure plz suggest me ASAP beacause in driving job many risk are there like accidents or fines etc i am getting only 800 riyal salary from where can i bear all this things.