recently moved to a new property

was given the existing alarm code.
entered code and nothing happened
entered code and pressed 2 for 2 seconds (under the 5 functions it is the only number listed and is labelled as away) - this seemed to arm the alarm with the usual beeping to get out of the building in a given time.
all good so far.

re-entered property and entered alarm code - doesn't work.
have tried all sorts of things but cant figure out how to disarm the alarm.

currently I have black tape over the sensors but would prefer to disable the alarm properly

I've been going over the manual but its more focused on the fancier LCD models.

I might be doing/missing something stupid eg enter pin and hold "xwyz for" 2 seconds but would be grateful for any GZers input or else I will need a pro to fix it.