bondseven

I have a HTC one for almost 3 weeks. I just realized that I had a LTE connection issue. Never paid attention to it before. The phone can discover the LTE signal (after toggling the airplane mode). However, it can not hold it. When I tried to use it, the network is switched to 3G. Actually, the signal level of LTE is very strong when this happened, -70 or -80dB. I felt that it is the firmware or configuration issue with the phone. Any person has a similar problem like me? I already told with Sprint and they can't solve the problem. Any sugguestions? I already updated PRL, profile. My area is officially lauched and I had the best signal (shown on SPRINT coverage map)