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Just got off the phone with them. It is a network wide issue and they are working on the fix. It should be done sometime tonight or early tomorrow in the AM.
I don't think Tesla would want to highlight their problems to people unaware that their app isn't working. What they should have done is give an error message that shows that the servers are down system-wide and not just only on your specific account/car.
It's been down for me since Sunday morning. Same error as everyone else. I called Tesla and was told they were working on it yesterday. Pretty sad it's taking this long to fix.