Trans tune questions/issues?

So my cars a 13 CTS-V A6. Ive been tuned with the same tuner for over a year now. Airaid CAI, Speed Engineering Longtubes, Lingenfelter Solid Isolator, Brick reinforced, Flex fuel sensor, ID850X .i made some changes smaller upper pully 2.45, Vadder Destroyer HX, Vadder 3 gal in bumper Expansion tank, EMP 2512a hx pump. after dialing in new setup he went over my transmission tune again and made some adjustments. I uploaded it to the car using HP tuners during my lunch break at work and went for a rip run and to log it. Car was AMAZING shifted great tight and fast. I sent tuner the log and got a reaponse everything looked great. this was at 730pm. i go to leave work at 130am and as im pulling out of the parking lot slow and it starts bangin each time it shifts to the next gear and from 3 to 4 it didnt even wana shift right away felt like i didnt have a gear then it finally shifted. i instantly pulled over and turned car off and uploaded my old trans tune in and all the problems went away. but before going back to my original transtune I tried resetting the adaptive while loggin it slightly helped but the car didnt like it. im at 75k miles and I wana fix this idk if its the tuning or my trans is on its way out. Any suggestions please and thank you in advance!