Smile 4g lte situation on s4 unlocked canadian model with ATT provider

Hi guys I am requesting a little bit of help. Ihad a s4 canadian variant ,tried many custom roms but still having trouble with 4g lte. I had the correct apn's but in "about device" i reached only HSPA or HSPA+ .mY device is unlocked and I"m using ATT service.Also I tried to flash another modem but It didn't change and I don't know why. I'm running on mk6 stock one.My rom right know is a based canadian one maple leaf I had installed xposed , wanam and many other addsand I had Philz recovery instelled. Am I missing something else? WHat I did wrong or what's steps I had to do to finish my Job..?>


thank's alot for your help!!!