Hey nebmosam,
Thank you for clarifying the issue, it’s appreciated.
Please use the steps below to isolate the issue a bit..
Restart your Mac in safe mode and see which icon shows when you charge your Mac: How to use safe mode on your Mac - Apple Support We want you to be aware that restarting in safe mode may take a bit longer than usual since it prevents some software from loading and does a check of your startup disk. You may also see some graphic anomalies on your screen as well.
Whether or not it happens in safe mode, restart your Mac normally to exit. If it showed the right icon in safe mode, see if it also shows after the normal restart.
If the issue happened while in safe mode or reappeared after a normal restart, create a new user account on your Mac. Once it’s created, log out of your own account then into the new one and test the issue there: Add a user or group on Mac - Apple Support
Please let us know the results when you're able.
All the best.