Follow this steps to reset your sony tipo, this method will wipe all the data stored in your device. make sure you did backup before you perform reset.
Get to know how to use trackid, playnow, factory reset, set the alarm, assemble the battery, insert sim microsd from sony xperia tipo user guide st21i / st21a
Performing a hard reset sony xperia tipo dual st21i2. before you do a hard reset you should try first to do a soft reset. if you have to do a soft reset and
Sony xperia tipo family get 2 product, one is single card gsm with code xperia tipo st21i (st21a) and the other one is xperia tipo with dual slot simcard gsm-gsm with
China android i9500 hard reset done. press volume + and volume – and hold power button press volume + select factory reset/hard reset delete all user data
How To Hard Rest Sony St21i
SONY XPERIA TIPO ST21i & ST21i2 with Safe Hard Reset? : Hard Reset
Unlocking | Modem Unlocking | Mobile: How To Hard Reset Xperia X8