The number on the left (e.g. 1) in the "Referral history" refers to the total number of people who have applied your referral code when signing up for their account.
The number on the right (e.g. 0) refers to the total number of people who have used your referral code when signing up and made their first booking with GetGo.
Only once your referred users have taken their first booking will your referral discount be awarded! You will then be able to see the referral discount automatically applied to your next booking.