Remove the SIM card and memory card
Try a different charger, cable, and power adapter
Charge the phone for at least 30 minutes
Clean the charging port gently
Perform a forced restart
Check for signs of life such as vibration, sound, or screen backlight
Connect the phone to a computer and check if it is detected
Use phone recovery software if the device is recognized
Try recovery through cloud backups
Check Google account backups for Android
Check iCloud backups for iPhone
Remove the battery if it is removable and inspect it
Replace the battery if the phone powers on with a new one
Use an OTG adapter and external storage tools if supported
Boot into recovery mode if possible
Use manufacturer repair tools if available
Take the phone to a professional data recovery service
Ask for motherboard-level data extraction if the phone will not power on
Recover data from the SIM card if contacts were stored there
Recover data from the memory card using a card reader
Avoid repeated power-on attempts if the phone is damaged by water or impact
Do not factory reset the phone before attempting recovery
Stop using the phone immediately if data is critical