New EE mini 4Gee - won't connect

[oldmanbm]

Have used the old 4G EE dongle for five years in the remote office in an adjacent building/ It has worked really well but I was tempted by an offer to up my data allowance (from 15Gb to 50 Gb) and less per month. I do't use it for streaming just normal office stuff. Anyhow EE tells me I have 50Gb I can use until the next renewal but for the life of me I cannot get it to connect to the internet! Any ideas?