Must be rooted do this for unlimited tethering:
1. Install terminal app
Settings put global tether_dun_required 0
Change: APN protocol ipv4
APN roaming protocol ipv6
here's a screen record link instructions on how to do directly from the phone.
* needs to be rooted and twrp recovery
* please make a back up before anything so you can revert back just in case. I'm not responsible if you mess up.
1. unzip file to phone sd card
2. from recovery go to (advance/file manager)
You gotta be s-off and unlocked and do the commands one by one in command promt. First time it will give u an error...re-do the command right away and it should work.
Also as an advise read the instruction carefully at least 3 times so u undest...