So, I downloaded n app called shortcut master lite cuz I member here on XDA recommended it to fix LTE issues. Don't know of his name but I will edit with his name for credit. But I turned advanced LTE on(u must search for it).Did not notice any difference in LTE. Tried it initially but did not have VOLTE while making outgoing call. But when a call comes in and I answer LTE stays connected. So I went back into the shortcut app and looked up LTE Functionality. Found a setting in there which says VOLTE Test UI then in that setting I turned on the first 2 options which then have me VOLTE both on incoming and outgoing calls. Not sure if it breaks anything but I have mine off cuz not sure if it breaks anything.