I have a 50 GB sim in a wi fi router which had been working fine in Spain until we used up our 12GB EU roaming allowance. I Paid £9 for add on data of 10 GB but the wi fi is no longer connecting and comes up with the message “This service is unavailable in International Roaming” We are now in Portugal with Smarty cards working fine in our phones. I have switched the router off and back on again and at first the wi fi appears to be working fine but after about 30 secs come up with the unavailable message.
I agree with @SmartyTrousers - it looks like you purchased the add on described on p14 of that Price Guide. This is designed for when you use up all of your plan data in the UK and need some more. It would allow you to use data for roaming, but only up to the 12Gb limit (assuming you had that much left).
