Firstly I have submitted a support request ....
I have a SmartSolar charger connected via Cerbo GX to VRM.
In the Victron Connect App via the VRM tab if I try to correct what seems to be the wrong battery preset (seems always to show "User Defined" ) and set it to Victron AGM / Gel the device reports an Error Code #119 instantly.
According to the error code list this error should never happen .....
It can be fixed by restoring defaults powering down PV, disconnecting battery and rebooting after a 3 min wait. Bit of a pain in that the reboot needs physical presence but not major.
Since this occurs consistently (well twice in my case) it seems to be a bug.
Prevention is better than cure, so it won't happen a 3rd time.