The warnings are just that, warnings that others you may have been interacting with or who can see your chat feel your behavior may be violating policy. To check your behavior against our policies.
If you haven’t been logged in those reports were likely from before you stopped playing and the message was never delivered, so it popped up when you logged back in.
Because of warnings? You aren’t suspended simply because of reports. It usually is due to the content of those reports being verified as containing inappropriate and/or toxic language.
The last one I can see back in February appears to have been appealed, reviewed and upheld. Meaning that we verified the reports again.
I am sorry that you have decided not to continue, Sushiroll, but I wish you well in wherever your gaming takes you.