AutoTools Switch between 2G-3G-4G

Hi to everybody.

Everything seems works fine with Autotools on my Xiaomi Mi6 with Miui 9 (not Oreo) and full rooted...
but...
when i try simply to switch from 2G to 4G or 3G or viceversa, nothing appens
untill when
i turn ON/OFF Airplane Mode.

I've already performed the adb shell grant permission via my PC and given full permissions to Autotools under Miui settings.

This thing is really strange, for example Automagic works fine, switch between 2G-3G-4G without problems..... but i want to use Tasker !!!!

Any idea ???