Front park assist works, but rear doesn't

[sasam1400]

Hi all.
Recently I had an accident and my Insignia (2011) was smashed from rear.
It took long time to repair, now I finally have it back, but rear parking assist doesn't work (although front side works!).
There was PARKING ASSIST FAULTY message on display before and park assist didn't work at all, neither front nor back. But after replacement of couple of rear sensors the message went off, and now the front works, but the rear not!
Any ideas?

[lizzard-t]

Take it back to the repairer
If it was working before then the onus is on them . I do feel .