How to link my credit cards to PBe? and How to get credit card e-statement?

I go to the website:

1. Account > PB Card >PB Card Summary, then I get

Error Code : (E0001.3B.2850350000)
You do not have the relevant account.

2. Payment > PB card payment > To Own Card, then I get

Error Code : (err00002.3B.2850363443)
Your Request Could Not Be Executed.
You Do Not Have The Relevant Account(s) For This Feature.

3. E-Statement Registration > Bottom got a link (For PB Credit / Debit Card member, please follow the steps here to link your card.) > I click the link then I get

Invalid Request
Thank you for using PBeBank.com

I have a Public Bank saving account but I did not specify it when I apply for the credit cards. The counter lady said Public Bank will auto find my saving account when they do background check using my IC. But I don't see anything in my PBe that links me to my credit cards. Then where will they credit the cashback to me? My Gosh, I swear Public Bank has the worst PBe and Mobile App ever. They are so not intuitive and super not user friendly. I wish we have something like Maybank2u app that works fantastic.