ZTE Rockethub MF279T not connecting to internet

[Woj]

Hi. I inherited a ZTE Rockethub MF279T today, I went into rogers and got the 5G home internet plan but it doesn't seem to want to connect to the internet. 

I am getting 4 bars and blue lights indicating a strong 4G connection, but in the Rockethub settings I get an error when I try to turn the 4g slider on. 

The Sim card was tested in another phone and it works fine there. The person at the Rogers store also tried putting their Sim into the rockethub and it lit up green instead of blue indicating an LTE connection, but it did work. He gave me another SIM to try but that one didn't give me any sort of connection at all. I'm not sure why only 1 of the 3 sims worked? I think the fact that it went into LTE instead of 4G has something to do with it.

I'm not sure if I've given enough info here but any help would be greatly appreciated.

Thanks. 

EDIT: additional info. When I try changing network settings to "LTE only" instead of 4g, I get red bars indicating no service. It seems like the rockethub prefers LTE over 4g and I can only get 4g through the SIM. Does this make sense?

***Edited Labels***

[Woj]

Here is a screenshot of the 4G slider that I pulled from the internet. I cannot get it to the green ON state shown.

[RogersMoin]

Hello, @Woj.

Welcome to our Community. Thank you for your detailed post and the screen capture.

I appreciate you testing the Rogers SIM on another device; it is a logical troubleshooting step. The problem could be related to the Rockethub being locked to the previous carrier. Even though you have inserted a Rogers SIM, the screenshot shows the device is connected to the Telus network. Please contact the original device owner and have them unlock it.

Please keep us posted.

Cheers,
RogersMoin