LB1120 question: how to use "device data" instead of "hotspot data"

I have set up my LB1200 with a sim card from a cellular device on my unlimited plan that I wasn't using. On this plan, there are two ways of using data on each line - the dedicated data for the device itself and hotspot data. The device data is unlimited, then after a certain amount used it may be throttled down in times of network congestion. The hotspot data is technically unlimited, but is throttled to an absurdly low speed after a smaller amount of data usage is reached. I don't know much about LTE networking, and I'm not sure how these devices differentiate between these data streams, but obviously, I want to use the dedicated device data as the source of my LTE internet on my modem, not the limited and throttled hotspot data associated with the line. I assumed it would do this by default, but I found out that it had used all my hotspot data instead of using the device data. How, if this is possible, might I go about changing this? It isn't much use to me as it is now.

Note about my configuration: I'm using the modem in bridged mode so I can use my Netgear R6220 Wifi router as a DHCP server and have access to its more advanced features like port forwarding, QOS, etc. Not sure why this would have any effect on my issue, but it may be relevant, I suppose.