"4G First" Network selection is disapear. How to fix it. Firmware 5.1.3.4G

“4G First” Network selection is disapear. How to fix it. Firmware 5.1.3.4G
Meizu M3 Note 2gRAM / 16gInternal memory

Have you tried Settings–>celluar networks --> network mode–>4G first?

ya, and there is disapear too. i can only change to 4G from ##3646633##. On 5.1.3.3G, the problem not occur.

This may be due to the laws of my country.

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