1. Turn off the phone completely.
2. Press and hold both Volume UP (and HOME) + power on the phone.
3. When Android Recovery menu screen appears release all keys.
4. Navigate and highlight wipe data / factory reset using the Volume down key and press power.
5. Navigate and highlight again to Yes -- delete all data and press power.
6. All data will be lost! Before doing a hard reset backup all important data.
After hard reset is done select Reboot system now. Press power to reboot the phone.
Another way to reset your Samsung Galaxy J2 Pro is to enter the reset code on dial screen.
On dial screen enter this Samsung Samsung Galaxy J2 Pro reset code: *2767*3855#
All data will be lost!
See Samsung Galaxy J2 Pro hard reset
Or
{Make use of|Employ|Work with} Samsung Galaxy Samsung Galaxy J2 Pro Backup and reset function
Go to Settings > {Back-up|Back up} and reset > Factory data reset: Reset to zero settings to the {manufacturing plant|manufacturer|stock} default values and erase all data.
Your device freezes or has {perilous|airport terminal} errors
{In case your|If the|Should your} device {stalls|interrupts} or hangs, you may need to close applications or reinsert the {electric battery|battery pack|power supply} and
turn on the device to regain {features|efficiency|operation}. If your device is frozen and unresponsive, press and
hold the {Electric power|Electricity|Ability} button for more than 8-10 seconds to {restart|reboot your computer|restart the pc}.
If this does not solve the problem, perform a factory data {reset to zero|recast}. On the Applications
{display|display screen}, tap Settings -> Backup and reset -> Factory data {reset to zero|recast} -> Reset device -> Erase everything. Before performing the {manufacturing plant|manufacturer|stock} data reset, remember to make back-up copies of all important data stored on the device.
