Affiliates + Membership 2 + Buddypress referrel problem

I set up the referral program with 10$ for signup to one membership and 5% for referring.

I set up paypal sandbox account for this.

I tried creating the user with that membership.

User is created, paypal deduction is happening but referral amount is not adding to the user.

And I checked the membership, there he is not adding to the membership.

Can you please let me know the issue?