PayPay bank account opening denied

I’m not sure why but PayPay just denied opening an account in their bank. They didn’t provide any concrete reason for this.

I’m an expat and wanted to open an account in the PayPay bank in order to be able to integrate it with PayPay mobile app.

I understand that I was denied for a credit card from them, but for a bank account? I just don’t understand what might have gone wrong with the application. This is just a plain bs thing in Japan.