[Android Q&A, Help & Troubleshooting] mark0021:
Hello, I really need help, I owned Lenovo Z6 L78121 and me, like the others who wants pushing their device limit to the the max. And we all know that you cannot do such thing without these first couple steps. The Custom Recovery and Root Access a.k.a. Super User.

So I try every firmware I've downloaded, I manage to have twrp and root access, but still sometimes some app still crashing then I accidentally checked the "Erase everything before download" then while flashing I notice different message in the log saying:

2020-08-03 22:52:39.864 22:52:39: INFO: fh.attrs.MaxPayloadSizeToTargetInBytes = 1048576

2020-08-03 22:52:39.864 22:52:39: INFO: fh.attrs.MaxPayloadSizeToTargetInBytesSupported = 1048576

2020-08-03 22:52:39.864 22:52:39: INFO: Issuing Erase

2020-08-03 22:52:39.864 22:52:39: INFO: _____ _ _____

2020-08-03 22:52:39.864 22:52:39: INFO: |_ _| (_) | ___|

2020-08-03 22:52:39.864 22:52:39: INFO: | | ___ ___ _ _ _ _ __ __ _ | |__ _ __ __ _ ___ ___

2020-08-03 22:52:39.864 22:52:39: INFO: | |/ __/ __| | | | | '_ \ / _` | | __| '__/ _` / __|/ _ \

2020-08-03 22:52:39.864 22:52:39: INFO: _| |\__ \__ \ |_| | | | | | (_| | | |__| | | (_| \__ \ __/

2020-08-03 22:52:39.864 22:52:39: INFO: \___/___/___/\__,_|_|_| |_|\__, | \____/_| \__,_|___/\___|

2020-08-03 22:52:39.864 22:52:39: INFO: __/ |

2020-08-03 22:52:39.864 22:52:39: INFO: |___/

2020-08-03 22:52:39.864

2020-08-03 22:52:39.864

2020-08-03 22:52:39.864

2020-08-03 22:52:39.880 22:52:39: INFO: TARGET SAID: 'INFO: Calling handler for erase'

2020-08-03 22:52:39.880

2020-08-03 22:52:39.880 22:52:39: INFO: TARGET SAID: 'INFO: invalid num_partition_sectors result -1'

2020-08-03 22:52:39.880

2020-08-03 22:52:39.880 22:52:39: INFO: TARGET SAID: 'INFO: Erasing the whole disk/LUN 2'

2020-08-03 22:52:39.880 22:52:39: INFO:

2020-08-03 22:52:39.880

2020-08-03 22:52:39.880

2020-08-03 22:52:39.880 22:52:39: INFO: ERASE SUCCESSFUL

2020-08-03 22:52:39.880 22:52:39: INFO: ERASE SUCCESSFUL

2020-08-03 22:52:39.880 22:52:39: INFO: ERASE SUCCESSFUL

2020-08-03 22:52:39.880

2020-08-03 22:52:39.880

2020-08-03 22:52:39.880 22:52:39: INFO: ==============================================================

2020-08-03 22:52:39.880 22:52:39: INFO: Files used and their paths

2020-08-03 22:52:39.880 22:52:39: INFO: 1 'C:\Users\Mark\AppData\Roaming\Qualcomm\QFIL\COMPORT_6\port_trace.txt'

2020-08-03 22:52:39.880

2020-08-03 22:52:39.895 22:52:39: INFO: _ (done)

2020-08-03 22:52:39.895 22:52:39: INFO: | |

2020-08-03 22:52:39.895 22:52:39: INFO: __| | ___ _ __ ___

2020-08-03 22:52:39.895 22:52:39: INFO: / _` |/ _ \| '_ \ / _ \

2020-08-03 22:52:39.895 22:52:39: INFO: | (_| | (_) | | | | __/

2020-08-03 22:52:39.895 22:52:39: INFO: \__,_|\___/|_| |_|\___|

2020-08-03 22:52:39.895 22:52:39: INFO: {All Finished Successfully}

Then when the flashing was finished, I checked the qfil config and there's a check in the "Erase all before download"

My device reboot normally like before, but the first thing Ive noticed was the wifi turning off after I think 10 seconds then turned on again. Then the Build number was unknown, serial no. was 111111111111111, IMEI 1 & 2 were none, means sim card will not work, proximity sensor , gyro not working means landscape not possible. so I think its "half-bricked" for ME...

Then I try your suggestion, I manually flash the persist.img in the fastboot flash command then suddenly my wifi now working properly, and the proximity, gyro were now good too,

My only problem now are Build Number, Serial No. and the IMEI 1&2.

What .img files do you think I should manually flash?