App signs me out

Same here, but I also have ongoing issues with my brand new Yukon Denali. My 2020 Yukon Denali I traded did not have this issue at all. I would sign into the app once and Face ID to access anywhere/anytime. Now, I am prompted for 2-factor authentication, often lose my user ID, have to re-authenticate with 2FA and repeat the cycle every time I hit a different cellular tower or wifi network. Then we get to the point of my PRE PAID unlimited plan having been removed from my account and the month I have owned the vehicle being spent waiting for them to add what I paid for back to my account. This seems to be a daunting task for the company that owns the system and service. Anyway, the app has gone downhill (this is my 3rd Yukon Denali) and support is non-existent. Best of luck to you Xzrpkb!