6l80 Transmission issues

[SSEman]

So I have this 2015 Camaro SS. And Its been having some issues. So recently My Car had a code on it that I scanned and was for the Torque Converter not locking and I could feel it aswell when i drove it.So I took it to the dealership and the dealership got it replaced as well as the fluids and now everything is good. It shifts to all the gears normally and locks normally as it should, it basically kind of feels like a new transmission. I test drove it, but it seems the only problem is that when I stop or go at idle the transmission disengages until i start driving again then it reengages. My brother is telling me it’s probably the shator pump in the Transmission and might needa rebuild but im hoping thats not the case. So I did some research and it said something about a Smell and a whining noise and codes that will appear if that was the case but I havent got any codes, Even through the Chevrolet Advanced codes and theres no hard codes anymore since I replaced the Converter. But I heard that due to low transmission fluid that can cause that low pressure so I checked and it was overfull. So it was drained a little, I let it sit and drove it again. It seemed to improve but then started again to disengage again. Whoever had a possible solution or experienced this please lmk. Currently theres no Codes or check engine. So im not sure if its trying to get used to the new converter or what but Ive taken it back to the dealership to correct the problem since I have a warranty on it.

[chriss2]

What do you mean by disengages?