Veritas alarm wont reset after power loss??

Had a power loss last night and the alarm flashing outside (no noise) and the keypad showing unset. Have been able to reset from this position before after an actual unset condition but now after the power loss the keypad is lit but keys not working.
Am wary of shutting off power in case this triggers alarm, anyone any suggestions? Or a reliable alarm specialist in the central Scotland (Cumbernauld area)
Alarm is a veritas but unsure of model, basic keypad with no display, sorry.

Any help appreciated.

cheers