F1s mất imei - Repair imei Online

 Starting META mode, wait...
 Restarting to meta,wait....
 If drivers missing, please install CDC drivers.
 This can take up to 5 min on slow phones.
 If take too long, check device manager for drivers.
 [146]META Port Detected: MediaTek PreLoader USB VCOM_V1632 (Android) (COM146)
 Start sync target, waiting responce.....
 ChipID: MT6750,S01
 Using Algo 3.
 Brand: OPPO
 Board: full_oppo6750_15331
 Model: A1601
 Name: A1601
 Release: A1601EX_11_A.33_170814
 Version: 5.1
 Platform: MT6755
 Start nvram restore, do not disconnect phone!!!!.
 NVRAM Retored OK.
 All done.