REFERENCE Oppo A83(CPH 1729) Passcode Done by Hydra (Meta Mode)

[Landon38]

Follow the image
on dropdown list select Meta Mode below there is a rebooter: select Metamode Auto and hit Switch/Reboot, wait about 10-15 seconds
After that Tick Factory Reset/Format Userdata, under Method/Option dropdown list select Factory Reset Emmc 1


after that phone is still Metamode, follow the reference image
under Rebooter dropdown list, select Meta to Normal and hit Switch/Reboot