This method is just different from the normal one you've been using.
Follow the steps below to format or factory set your Tecno L8 and L8 plus. This method is also known as 'hard reset'.
Switch off the phone
Press and hold the 'power' + 'volume down key' simultaneously. As you press and hold the two button simultaneously, release the 'power button' once there's a splash screen (TECNO), while still holding the 'volume down key' until you see "Factory Mode".
Please take note, this step is very important and strict, otherwise you have to redo it until you get it right.
Wait for few seconds for options to show up.
Use the volume keys to select up and down.
Select to 'Clear eMMC' and press 'power button'.
That's all, wait for at least four minutes for it to boot.
If you have any question you can ask here.
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