Interesting problem after repairing broken screen

[Juzzo]

So I dropped my 930 and doing so the glass/digitizer/lcd shattered... Well being a handyman I ordered a new glass/digitizer/lcd combo with frame from the good ol' Ebay. Switching all the internals from the broken phone to the new frame went according to plan, phone fired up like it should and all was working like they should... But now couple days later, I noticed an interesting bug: When I try to call someone I get a "no network" notification. So I end the call and behold the 4G network is restored. Data connection works, and I can make a WhatsApp call, but not a carrier call.... Weird
So next I checked that all settings were as they should, all as should, then I tried switching to 3G and 2G. Boom, nada! No network for both of them, only the 4G works! Haven't yet done the hard reset, because I thought some of you might have other ideas on what might be the underlying problem. But if all fails I'll do a hard reset first and only then try to upgrade the phone to WP10.

Thanks in advance - J.

 

[xandros9]

If it were me I'd do a teardown and make sure all the antennae and other wires are in order.