Helium SIM in 5g router constantly cycling IP address/disconnecting

I put my Helium SIM in a 5g modem/wifi router to see if I could use it from there, as it has external antennas and gets better reception in the rural area I am in.

I set the APN to helium-mobile, and it can see the T-mobile network and connect but it refreshes/gets a new IP almost every 2-3 seconds and constantly disconnects. I got the APN from the helium support site.
Tried forcing it to ipv6 and 4g, but similar results.

Any idea if Helium looks at the IMEI of the device and says I can't use it in a hotspot/modem and only phones? I had it in my ipad and it worked fine...

Its the $30 new plan if that matters.