Tips and tricks to fix OPPO F21 PRO (problems. This phone has good vivid color display because it is use AMOLED screen type with 6.43 inches size. The refresh rate is 90Hz for smooth scrolling and transitions. This phone is powered by Qualcomm SM6225 Snapdragon 680 4G, therefore we can not use 5G connection for Internet access.

This phone can work with dual simcard for different phone numbers. It has triple rear cameras and single front camera 32 megapixel with punch hole at top right screen. We will give more solutions and information about how to solve troubles of OPPO F21 PRO (CPH2363) at community.


What are Advantages of OPPO F21 PRO Specifications and Features?

  • Network GSM 3G HSDPA or 4G LTE with Dual simcard slot
  • LLCD 6.52 inches 20:9 aspect ratio
  • Processor Octa-core 4×2.3 GHz Cortex-A53 & 4×1.8 GHz Cortex-A53
  • GPU PowerVR GE8320
  • Bluetooth / GPS / Wifi
  • Memory Internal 32 GB
  • RAM 3 GB
  • Main Camera Triple 13 MP f/2.2 + 2 MP f/2.4 + 2 MP f/2.4
  • Main Camera Features autofocus, LED flash
  • Front Camera 8 MP for video conference and selfie photography
  • Operating System Android 11
  • Battery Li-Po 5000 mAh



How to Fix or Problem Solving for Recovery OPPO F21 PRO hang or not responding or malfunctions or stuck or freezing or bricked ?

With 128 GB internal storage, there are many games and applications that we can download from Google Play Store. Please read many user reviews before install new or not famous applications. Because some of them may contain viruses or malware or threat that can make troubles if installed on our OPPO F21 PRO like hang or freezing or become slowly or stuck or broken or LCD touch screen not responsive. These kind of apps will not get Verified by Play Protect information / icon.

What do we have to do? Please try to remove temporary files and caches from internal memory by performing soft reset or reboot. We might get some help from antivirus applications like AVAST or NORTON to find suspected application and fix some bad setting options.

We also can clean temporary files and caches anytime by performing reboot or restart. This procedure will not remove any installed applications and important data, therefore we can do this process anytime we want. Please do not install APK from unknown resource for safety reasons.


How to Force Shutdown or Force Soft Reset or Reboot or Restart OPPO F21 PRO ?

Big RAM will give better multitasking performance. This phone has 8 GB RAM. However, some other installed applications also can get hang or make LCD touch screen not responding. We have to force reboot or soft reset or restart by press and hold POWER button until OPPO F21 PRO (CPH2363) turning off or shutdown.

Performing reboot or restart is recommended anytime we want, because it can help to make our OPPO F21 PRO become faster. It will remove any temporary files and caches. All applications and data will not removed or wipe because of soft reset or reboot or restart.



How to backup data or Contact at OPPO F21 PRO ?

This phone has external memory slot for MicroSDXC memory card. We can copy and paste all important files, photos, videos from internal memory using Android file manager.

We can use USB data cable to connect with computer. After our phone recognize by computer, then choose important files using computer file manager and copy to safety location at our computer. We also can connect OPPO F21 PRO with flash drive at USB OTG port.

If our OPPO F21 PRO has already signed in with Google account, by default our contact will be synchronize in the background to Google server. Please make sure we check all contact at Google contact server using Internet browse to make sure backup is done.


Please note: These options below may not work for some devices because of firmware update version or hardware troubles or some other possibilities.

#Option 1, Hard Reset OPPO F21 PRO with software menu

  1. Turn on the OPPO F21 PRO
  2. Make sure the battery is not empty
  3. Backup important data at OPPO F21 PRO because all data and applications will be erase or delete
  4. Go to Menu :  Setting 
  5. Choose Tab : General
  6. Press Backup & Reset > Restore factory setting
  7. Better you not check anything at the option if you do not want to erase data at data partition at internal memory
  8. Choose Reset phone 
  9. The OPPO F21 PRO will do the master reset process.


hard reset oppo f21 pro


#Option 2, Hard Reset OPPO F21 PRO Factory Default using Hardware Secret Button Key

If we can not go to menu, or OPPO F21 PRO can not turn on or hang or stuck or frozen so we can not access the menu setting or nothing happen while touch the screen, then try to factory reset with secret button and hardware key

  1. Turn off the OPPO F21 PRO
  2. Make sure the battery OPPO F21 PRO already full or more than 50%
  3. Press together and hold the Power Button + Volume Down Button
  4. If the Logo appear, then release the button, after that we will enter some menu
  5. Choose wipe data / factory reset using Volume Button, and press Power Button to Enter or OK
  6. The OPPO F21 PRO will continue master reset, wait for several minutes until OPPO F21 PRO start like new again.


How to Unlock or Fix or Bypass or Solutions for OPPO F21 PRO forgot password code or security lock screen pattern or pin (lost password)?

There are some data and applications that need to be secured from unauthorized people. It is including our private photos videos that shoot with triple back side cameras 64 megapixel for wide + 2 megapixel for macro + 2 megapixel for depth of field or bokeh blur effect. We can use fingerprint or facial recognizing.

We need to activate secondary protections for backup like screen lock pattern or pin or password. Because OPPO F21 PRO fingerprint or face detection will not work after reboot or restart. It will ask secondary protection for unlock. However, the problems will start happen when we can not unlock this phone or fingerprint can not work. What should we do?

If we forgot or can not unlock OPPO F21 PRO security protection, then nothing we can do unless doing hard reset or master format using hardware button combination key like steps at #option 2 above. For more security protection, latest Android version has FRP (factory reset protection), therefore it will ask for previous Google account username and password to bypass FRP question.


If we can not turn off our OPPO smartphone, then please force soft reset or reboot by press POWER BUTTON + VOLUME UP BUTTON for several seconds (usually less then 10 seconds) until this phone reboot by itself.


Is That Any Secret Code for Doing Format OPPO F21 PRO ?

There is no secret hidden code for OPPO F21 PRO to make it back to factory default. We need to choose one following options above to hard reset.


How to Format or Erase Phone Memory at OPPO F21 PRO ?

When we need to remove or wipe any data and applications from OPPO F21 PRO, then please performing hard reset or reformat. Please choose Erase all data / Internal storage when our phone has that menu. Performing hard reset or reformat will remove any registered Google account from OPPO F21 PRO.


How to Make Battery of OPPO F21 PRO Stronger, Life Longer and Not Fast to Drain ?

OPPO F21 PRO (CPH2363) has 4500 mAh battery capacity. We can use it full one day without need to recharge. We have to do some adjustment if we want to use it more longer such as playing games or watching movies several hours continuously. Please make LCD screen not too bright or disable all not use connections like GPS or Bluetooth or Wifi. NFC is not available on OPPO F21 PRO.