Accenta 3 Fitted New Battery Problem With Zones!?

I have recently fitted a new battery i managed to reset the number and i could turn the alarm on and off.

When i went to bed and tried to omit zones i wouldnt set? Then after about 40 minutes the alarm went off and the only way to turn it off was to take the battery out.

Do i need to reset the zone, if so how?

Or is there a more serious problem?

Thanks