So I purchased a sim many years ago on eBay which gave me 12 months worth of data for my mifi device (unlocked) on T-Mobile (1gb data, unlimited browsing). I used it for a couple of years until the mifi died. I've now purchased a replacement and it says I don't have enough balance to use the data (6MONTHSWEB). I called EE and they said this sim needs to be used in a phone - but I had been using it in a mifi for a couple of years.
Does anyone know what the best option for me is? I can't return my mifi, so should I buy a phone just to hotspot? Should I buy a sim (these T-Mobile sims are pretty rare now) or is there a way for me to fix the issue?