Check out how to easily wipe cache partition in CoolPAD N5C. This operation won't affect your personal files it will only remove temporary cache files. As a result you can refresh Android 8.1 Oreo system and optimize MediaTek MT6739.
Firstly, turn off the smartphone by holding the Power button for a couple of seconds.
Then push Volume Up + Power key for a few moments.
Release buttons when the CoolPAD logo pops up.
Now choose wipe cache partition by using Volume buttons to navigate and the Power key.
Wait for a short while and select reboot system now with the Power button.