Referral Link Problem

Hi,

I switched to Bulb on the 14th of October through a friend´s referral link. It has now been more than 21 days and when I check on my account, it does not show the 50 pounds I am supposed to get from Bulb but says I have 0 pounds credit for referring friends instead. How do I get these 50 pounds and when will I get them?

Thank you.