EX3700 connect to T-Mobile TMO-G4AR router issues

[JasonSJ]

Hoping for help. I have a new internet provider (T-Mobile), using the T-MOBILE-G4AR router/wifi and I seem unable to connect my Netgear EX3700 to use as a range extender. I can get into the EX3700, I see my networks enter the WiFi passwords and get a “ The Extender was not able to connect to your existing network.” notification. I have tried several times and have done factory reset of the EX3700 a couple of times all with the same end result.

[plemans]

Are you using the installation assistant through the browser? 

that's about the only way I've found it works with the tmobile gateways

[JasonSJ]

Hello, Yes, with the lack of a WPS button on the TMO-G4AP router I believe that is the only option. I have tried many times, I seem to be able to set everything up with no issue. I have updated the Netgear EX3700 to the latest version. But I can not get the EX3700 to connect to the TMO-G4AR, see screenshots below. Any advise on what might be the cause?

[plemans]

retry running setup with the installation assistant. Not the app.

Factory reset it (push and hold reset for 7-15 seconds while powered on)

Here's a video of how to use the assistant. 

https://www.youtube.com/watch?v=yJVklshxBMk