Oppo A5 (CPH1809) uses a Qualcomm Snapdragon processor, which allows it to be flashed or restored using the Qualcomm Flash Image Loader (QFIL)
To flash the CPH1809, you must use tools designed for MediaTek (MTK) hardware. Flashing Requirements for OPPO CPH1809 oppo cph1809 flash file qfil updated