Hi there, I'm not to familiar with this error so it's just a rough guess.
(1) Reinstall TruckersMP Launcher, https://truckersmp.com/download
And have you ever been banned before in the past you may want to consider reading this
https://forum.truckersmp.com/index.php?/topic/49295-api-returned-invalid-content/
Thanks, Toby.
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