ZTE router won't connect to network

[JordanR_2370461]

Hi guys, I've just got a ZTE 4g router and a smarty unlimited data SIM but it will not register to the network, I've changed the APN settings and tried everything else I can thing of but it will still not work? Anyone have any suggestions or came across similar and find a solution? Currently have no internet access so need a speedy solution, SIM card is active etc. 

Thanks.

[MSF]

@JordanR_2370461   Is this any use? - https://manuals.plus/zte/mf263-lte-4g-router-manual#access_the_internet

[JordanR_2370461]

Unfortunately not no, I've tried everything suggested by zte and anything I can find online by smarty and still no joy, the 3/4g light on the router is just staying red and will not connect his is the 2nd router and SIM I've had now as I thought there was an issue with one or the other but it's still the same outcome so I'm now at a loss. Thanks for trying to help though.