LTE not working on OP3

Hi,

I got my OP3 on Friday. Everything seems to be great except that my LTE doesn't want to work.

Usually putting in the sim card did the trick (HTC M8) and LTE was set up. On the OP3, I only get 3G and H connectivity and it jumps between the two.

I tried to manually add the APNs but the result is the same. Anyone else have this issue?

Thanks!