Pay as you go wifi - credit activation help needed

[SJMISO3]

I have purchased £15 of credit (top up) for my PAYG WiFi SIM and can't figure out how to activate this so that I can actually use the data. When I try to do it via the app it asks for the EE mobile number to verify via  text message. I don't have a mobile phone on the EE network, just the pay as you go mini router/dongle. For the same reason I cannot call 150 to activate from my mobile, unless I have to remove the SIM from the device and switch it into my current mobile (on a different network currently) which seems like such a faff. There must be a way to do this online? Any suggestion much appreciated. Thanks in advance.  

[XRaySpeX]

@SJMISO3 : Mobile routers contain a SIM. All SIMs have a mobile no. Visit http://add-on.ee.co.uk/status from a device connected to your mobile router by WiFi to see your data & credit status as well as its mobile no. at the top.