Hi i have 2015 chev or holden captiva 2.2 diesel

I need something to read trans temp to do a fluid change.

I bought the pro version as other people have used it and said it works.

I installed, paired and did the GM PID install to get GM PID’s

At first the trans temp widget showed 80’C but for some reason glitched and showed -42 and didnt move.

I uninstalled and reinstalled, unloaded PID’s basically reset it and got it to work but shortly after turning bluetooth off or car off and on a couple times, it will go back to -42 exactly or sometimes no reading at all.

Anyone know why this could be happening?