3rd party sim ICCID invalid

Hi, i am trying to set up an Asda Mobile sim for my particle electron but when I put its ICCID number in on the setup page it says it is invalid though it is the correct lenth long and the sim is activated with credit on it, any help to why this would be happening would be great as generally Poarticle Support takes ages to respond to a ticket.

It’s not necessary to use setup.particle.io with a 3rd-party SIM card. You can just use the instructions here instead: