No communication to vats alarm system

No I don't have any codes that are u codes or loss of communication the truck runs
good and there are no securety light on . I am able to communicate with all other
modules except theft module also when I do a automatic scan of all modules it sees
thaft modle but it dose? not displayit once it scans ,
I worked on a previous: 2001 chevy tahoe 5.3, and on that one it did scan corract I was
able to scan the thaft system and was able to get pids and codes I'm thinking it may
be a bug for the