One m7 signal problem

Hi! It would be great if someone could help me. First of all ,I took this phone in exchange ,and it was already rooted,s-on,tempered unlocked. But ,I have problem with signal-doesn't work 3g and lte ,only 2g with full signal strenght. I installed custom rom Insert coin,because i have no 25usd to pay for sunshine to s-off phone to get it back to stock.. also,i have googled for this problem,and found that it possibly has something to do with radio signal,but didn't found any solution. Htc is all new expirience for me,because i haven't had opportunity to work with it before.I would really appreciate if someone could help me or adress me to solution topic. Cheers! 😃😃😃 p.s. sorry for grammar errors!

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