I've tried to add a RPi recently and had trouble loging in with google using ssh, that's an altogether different post, now I tried to remove that RPi instance but nothing shows and I can't add one either as I get the pop-up: You've hit your 1 Linux device limit. How can I solve this?

You've hit your 1 Linux device limit but nothing shows

pert July 26, 2019, 11:00am 2

I think you're encountering the same bug as reported here:
https://forum.arduino.cc/index.php?topic=626992

I've reported the issue to the Arduino development team.

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