Error on Checkout page

Hello,

It's really frustrating that following error comes whenever I try to submit checkout page to buy iPhone 12 ProMax with 24 months 0% APR installment funded by Barclays. I tried at least 50 times in last 2-3 months.

I contacted Barclays and they say it's issue with Apple as page is owned by Apple.

It doesnt specify what is the error and I checked all fields and everything is correct.

Error message is :

"There’s been an error with the information you provided. Please try again."

Link: https://secure2.store.apple.com/uk/shop/checkout?_s=LoanApplication

Can anyone help me what is the issue? I am sure all fields are correctly filled.

Thanks.