When your friend subscribes to Fizz using your referral code, both of your referral bonuses will be pending until your invited friend becomes a paying member. Same goes if you're the one who was invited: your bonus (and that of the Fizz member who invited you) will be pending.
When the invited person completes their second monthly payment, they will receive their referral bonus. From there, the referral bonus of the Fizz member who made the invitation will be applied on their next payment.