2012 Volvo VNL670 iShift not going into reverse

Hello,

I have a 2012 VNL 670 iShift that stopped going into reverse.

In R1 it doesn't really move/hops a lot. In R2 it seems to be working fine.

Tried going through all of the gears in manual mode and they seem fine too.

Does anyone know what would need to be replaced/fixed for this issue?

Also is it ok to use R2 for a short period of time until I can find out how to fix it?

Thank you