Press did then the master code
If you don't get the options to view the log, change time & date, add change user ect....
You don't have the master code
You can't change users via engineering menu
I'm certain I saw the BT Visonic alarm being sold in in PW World or Argos over 10yrs ago
I would be very surprised if any one at BT even knew they once had it as product
bin it,
they appear to become unstable with age & do weird stuff
fully default it & start again however the weirdness comes back...
(in my personal experience )