Car Alarms: 1998 mustang GT alarm, clutch work, alarmtek

Question
I have a 1998 Mustang GT The stock factory alarm is no longer being tripped by the keybob.  The alarm will set itself, but the keybob will not disarm.  The keybob will work door locks trunk and panic.

PS the car recently had clutch work.

Answer
Please be more descriptive if possible.

"GOING OFF?"

I need to determine whether it's a factory alarm
issue or, if it's an aftermarket system you are
dealing with.

Is it: Headlights flashing, car horn honking
and a worded SECURITY" light in the dash flashing?
(doubtfull since none of the notes show this
car as having a factory alarm system)=FACTORY

Or,

is it: flashing parking lights,
an LED in the dash area, and a siren
going off?= AFTER MARKET

Let me know more on this to better
advise you on a course of action
to take.

Best Regards,

Robert Martin
CEO/ALARMTEK
CARALARMMAN.com