Transfer case not dis engauging ?

[Dunk]

Ok have an Nw was in 4h today l went back to 2h when l pulled up and then stopped when l started car again and reversing it was nearly like hand brake was on shuddering lights were flashing on dash anyways stopped car re engauged 4h then back to 2h all was good mind you this only happened whilst in reverse ? Could this of been that between 4h and 2h it had not slotted back to 2h properly