Max BR1 mini, at&t prepaid sim card...cannot get wifi working properly

So this has been nothing but a trainwreck so far, mainly because at&t prepaid is just horrible. Just know I have access to my prepaid account and show I have 15 Gb of data in the account (this is just atrial run to see if things work properly). Anyway, I have my at&t prepaid sim card in slot A, shows connected to AT&T LTE with a couple bars. The location it shows me at on the dashboard is correct too so I know we have some connectivity of some kind. So under AP i set up my own wifi…give it a name, set the password, set the security policy to WPA-WPA2 - personal, all good there. when I try to connect to the wifi I log in with the password I set then I get this page:

Mind you I have already activated my prepaid sim card, my account shows active and everything. I have already restored all factory settings and set it up again and still get this screen…basically the wifi from the Max BR1 mini is unusable.
Soooo…anyone else had similar problems and figured out haw to make this work or does this thing not work at all with AT&T? The plan is to have a Tmobile prepaid card in slot B also but if I can’t get this to work at all no sense of wasting more of my time on a brick.
Also as a side note, I plug in my laptop to the LAN port of the Max BR1 mini and I have no connectivity to the internet. I tried to run a speed test and it never starts, just says there is a problem with the network. So it really seems that there is an issue with the at&t network with this Max BR1 mini.

A quick little update…so i took the sim card out of the BR1 mini and put it into my phone and I cannot access the internet either, and I get the same log in to activate your prepaid account screen…so it’s an AT&T issue for sure…but if anyone has had first hand experience with this please let me know.

I have an update!!! So I went to t-mobile last night and got a data only sim card for hotspots. Got the account activated and all. Put it into the BR1 mini and all i get is Optaining IP Address. Now I don’t have any other T-mobile device I can try this sim card on so back to the store I will go today.

now in the meantime with this att prepaid sim card I do have an att Sierra Wireless hotspot. I put the prepaid sim card in and I get the same issue as I did with the BR1 mini…when you try and log into the wifi it sends you over to the page like I posted above. SO now I know it’s on the att side of things that isn’t right.
Today just out of pure frustration I put my sim card out of my cell (att network) and what you know it works fine! I can log into the wifi now and access the internet.
So it seems that you need a cellular sim card and not a data sim card. I’m gonna assume it’s the same way on T-mobile but I will have to wait another day to test that theory.