I would start by checking the charger. Then I would start by unplugging and plugging back in. If that doesn’t work I would try a different charger. Next I would try a reset.. Then I would call Rivian for help If it still isn’t working.
I've never seen "maintaining range" before. You didn't accidentally set your charge level down to 50% did you? Looks like the latest app took out the "save" button and it'll change just by moving the slider now.
try a level 3 charger, if that works it's something with the 'charge box' (non technical term). I had same thing. Rivian picked up on Tuesday, and dropped off that same friday.
Also mine turned red and said vehicle error in the app.
If a home charger, turn off breaker and retorque all connections between breaker and charger (including in charger). They expand with the high volt load. I had charging problems and discovered the breaker connections needed retightebing. No issue since.