Reset PRAM: Reset NVRAM or PRAM on your Mac - Apple Support
Settings that can be stored in NVRAM include sound volume, display resolution, startup-disk selection, time zone, and recent kernel panic information. The settings stored in NVRAM depend on your Mac and the devices that you're using with your Mac.
Reset SMC: How to reset the SMC of your Mac - Apple Support Choose the appropriate method.
Resetting the system management controller (SMC) can resolve certain issues related to power, battery, fans, and other features.
Startup in Safe mode. https://support.apple.com/en-gb/HT201262
To leave Safe Mode, click in the menu bar and choose “Restart”