Hi all. I have the a few sm-g998b phones, rooted with magisk, and I am a bit confused about which CSC I should flash to the device (SAMKEY). I ordered the phones from Singapore and need them be more compatible with USA verizon and USA tmobile. Only using one sim per phone. Which CSC should I replace the current SIN csc with for each, and is there anything else I can do to make these phones play a bit nicer in the USA? I am currently having issues with no 5g, poor wifi calling, no updates, etc.