Hardware Help switch turning off mid game after updating system

[DualBladedKirito]

Hello. two weeks ago I updated my switch from 4.1.0 to 5.1.0. Everything was going fine until yesterday. It first started in xenoblade chronicles 2. I would play the game for about a half hour or so in handheld mode sometime even less time than that. The switches screen will go black and shut off. the power button is unresponsive until I plug the system into the wall. This only happens in game and not on the switch's home screen. Everything ran fine before. Don't know what;s causing the problem. Any help or advice would be very much appreciated.
PS It should also be noted that I upgraded my micro sd to a 128gb at the same time that I updated