Phone calls does not work on oneplus one, cm 13

Hi,
I am usually a reader but on the last few month I am facing with signal problem on oneplus one, cm 13.
After a lot of searching I finally isolated the problem:
4G works fine- only data
H+ works fine when there is fully signal. Usually makes problems.
G works fine data and calls.
H- calls works only if there is fully H signal, 90% from the times if there is not full H signal phone calls are not able.
This what I tried to do:
I changed to lte/gsm, and made the default network 3G.
Notice ***: when I try to make a call the network changed from 4g to H+ or H, and after few seconds it shows call ended.
What I tried to do:
1. Factory reset - did not solve the problem.
2. Change mobile company- did not solve the problem.
3. I rooted the device and unlocked bootloader, then through twrp 2.8.3 I flashed 44s modem flashable, and it only broke my proximity sensors, then I flashed tugasensorsfix and it repair the proximity sensors. But still I can not call people!! Only on 2g but Who can live on 2g network??
I am desperate to help, I will appriciate any Kind of help.
Thank you,
Ido Levi! .