How to force a factory reset or hard reset on Jiake devices

Jiake JK750 Jiake JK750
Jiake M4 Jiake M4
Jiake M5 Jiake M5
Jiake V19 Jiake V19
Jiake M8 Jiake M8
Jiake M6 Jiake M6
Jiake MX5 Jiake MX5
Jiake N9200 Jiake N9200
Jiake S1 Jiake S1
Jiake A8 Plus Jiake A8 Plus
Jiake S700 Jiake S700
Jiake L8 Jiake L8
Jiake A8 Jiake A8