I'm usig Sony Xperia XZ2 Compact (last 5 inch android from Sony) and i think i solved (or it solved itself) the 4g-Volte problem on it. Sony XZ2 phone is on Volte support blacklist at Smarty, so 4g calling should not work, but i didnt want to give up...
Yeah its a bit complicated, especially for casual user. Actually i was about to leave Smarty, already found another provider where i would port my number to, but looks like im about to stay :). I really didnt want to buy new phone as mine is the last...
