[Question] DOOGEE DG300 GSM/WCDMA network problem

[Aksom16]

Have you tried adjusting your APN settings for your network?

yes, ive configured my APN. However there is somthing like "Preferred networks" its empty. I tried to get another same model phone and backup the entire rom and install it on my phone, no luck still the same. Can u tell me how can i backup the entire FIRMWARE with NVRAM of the phone? Ive seen some on the posts by other guys, but im missing the CACHE file and the USERDATA file.

A couple of things to try here:

First, you noticed that "Preferred Networks" is empty. Since the SIM itself (typically) registers itself on the network, it may be the SIM itself. I'm going to assume that you tried "Network operators" and "choose automatically". Also that your APN is correct, data connection is on with the correct SIM selected, 3g service is enabled to your correct SIM, the network mode is 2g/3g (auto).

Secondly, make sure (assuming your device has two SIM slots) to try both slots! It may be the slot or the SIM, all should be checked.

Finally, it wouldn't be a bad idea to download Mobileuncle Tools. Once installed, go to "Engineer Mode", then to "Engineer Mode (MTK)", then "BandMode", after this, select your correct SIM#.

Inside this sub-menu is a list of frequencies that your phone is capable of. You will want to see if all the available frequencies that you need are checked. I assume that they are, but it is worth a shot.

So, in conclusion, your first steps in troubleshooting are: Check settings, check SIM, check slots with SIMs, check frequencies.

thnaks for the troubleshooting steps. Ive tried various things to get my network coverage work well.. such as:

1. Try my own sim on other device(which works great)
2. Try another SIM in my device(With the same issue)
3. Reflash the device with Original rom ( I lose my NVRAM as no MIEI, and got the NVRAM error wifi thing)

Im about to copy another (same model) device firmware to flash it into my device. The main problem here is that ive used both methods of backing up
1. Create ROM_0 from SPFlash tool> Convert it with Droid tool
2. Create backup using Droid Tool and convert it to Spflash tool support

The problem with that, it does not give me the full backup.
Please refer to attachment of the screenshots.