Good afternoon/morning

My problem is the following and I haven't reached a mechanic that can bring me a good solution:

Due to a mechanical mistake (the driver front driveshaft partial removed from the transfer and then it broke), my car was left working only with rear traction, this cause some damage, the problem now is that when I turn my car it works with the 4wd and vibrates, a mechanic suppressed the driveshaft (from the transfer to the differential lock) and now is working only with frontal traction, I want to know if you could help me with the most commons part or parts that are needed to be changed in order to make works again the 4wd.

Thanks in advance