Hope you meant CIF ID when you said customer id.
Anyways first, log in to internet banking, then open SBI Rewardz within netbanking (click on recent 10 transactions). It won’t ask for your credentials when you access Rewardz through netbanking. It should work.
If it still doesn't open from netbanking, it means SBI hasn't shared your data with the SBI Rewardz team. So, now you have two options:
1. Sometimes, it takes 2 months for SBI rewardz to work, so you can wait another month.
Or
2. You can email SBI Rewardz team and tell them that you created an account on 11th march 2025, and are unable to register on SBI Rewardz due to error.
Note: When emailing the SBI Rewardz team, make sure to include your Error Screenshot, CIF ID, your registered mobile number with the bank and your account number.
They will create the account for you from the backend.
Ps: Don't try to open SBI rewardz from Yono app, it will most likely throw an error too which can take forever to get fixed.