Traverse transmission acting strange, hoping it's not the worst case

My 2018 Traverse has started doing something that's making me nervous. When I'm at a steady speed and give it a bit of throttle to overtake, the revs climb but the car doesn't accelerate like it should, almost like the gearbox is hesitating. It only happens occasionally but it's happened maybe five times in the last month. No warning lights yet. I've been looking for the best Chevrolet repair garage in Khalifa City since I'd rather deal with it now than wait for something to fail completely, but I'm scared of what they'll tell me. Has anyone had this on a Traverse or similar GM with the 9 speed? Was it a fluid issue, a software thing, or did it turn out to be the transmission itself? I'd appreciate any honest input because I'm trying to prepare myself for the diagnosis.