Turn on airplane mode
Disconnect from Wi-Fi and Bluetooth
Restart the phone in safe mode
Uninstall suspicious or recently installed apps
Remove apps that have unusual permissions
Clear browser data and download history
Delete suspicious files and downloads
Run a trusted mobile security scan
Update the phone’s operating system
Update all installed apps
Change passwords for important accounts
Enable two-factor authentication
Back up important data
Factory reset the phone if the problem remains
Restore only trusted apps and data after resetting
Contact the phone manufacturer or carrier if needed