WiFi pod won’t register

[Mandylou66]

I recently upgraded to Sky Max hub. Unfortunately this has provided worse coverage throughout my house than the previous hub.

I reported this and was sent a booster pod. 
however the booster pod will not register via the my sky app. Each time I enter the serial number I get an error message but it's definitely the right number. 
is there an issue with this at the moment? 
thanks