I have ZTE phone:
Model z828
Fcc id srq-z828 IC 5200E-Z828
H/W U06A
DATE 03/2017
and have inserted and mounted a 32 GB SD storage chip. However, cannot seem to get an option to use adoptable storage.
In settings, storage I see options to unmount or format the SD card -- but no option to adopt.
Operating System version number: 5.1.1
Your model ships originally with Android 5.1. Adoptable storage was introduced in Android 6.0 .
So even if you update to Android 6, is probably that you wont have the option.
Also some manufacturers, dont allow this option, so if the option doesnt appear, or the option to move apps to the sd card doesnt appear, the option is not available.
It happened to me on a Galaxy J5 2015 with Android 5.1 that got the Android 6.0 update, and still doesnt work.
Hope it helps.
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