I have recently facing an issue of bootloop in my zenfone selfie z551KL if i flash will it remove all my data from phone or just wipe OS.
Thank you for your asking. Please primarily check if your google account or microSD card have auto backup your data if you can not access the phone.
Then kindly try the following steps to access recovery mode for the Factory Reset:
0. Try to back up your data with USB cable
1. Power off the phone, then keep pressing "volume down key"
2. Press "power key" and stop press " power key" once you feel the vibration. Still keep pressing "volume down key".
3. Stop press "volume down key" once you enter [Android Recovery] Screen
4. Choose "Wipe data/factory reset">"Yes"
5. "Reboot system now"
#Hardware Reset Guide
Please note that once the steps are completed, all data, apps, settings and personal information will be deleted.