Wireless Joint

Is there a data only SIM for a router that has no data cap? I have Calyx Internet now with the hotspot tethered to my router by USB port. The little hotspot has no reliable way to attach an antenna. I am not allowed to remove the SIM card. My router can take an outdoor antenna and I live in a rural area with a weak signal.

Moving the SIM to another device, has been done by myself and many many others for years with Calyx. They just can't support or warrant the new device is the real reason they don't want you to move it, no other reason that has any merit.