M5200 No connectivity without external antenna

Today my M5200 has decided it cannot connect to a network without using an external antenna. I disconnected my external antenna earlier and since then the device won’t connect to the network without it - the moment I reconnect it then the device works fine. I’ve tried factory reset.

This issue has been covered more on this topic but has been closed https://community.netgear.com/t5/Cell-Service-Mobile-Hotspot/Nighthawk-MR5200-M5-We-need-your-feedback/td-p/2170780/page/10