Don’t have credit card for more storage
Don’t have enough storage
cant back up
iPhone 12
Don’t have enough storage
cant back up
iPhone 12
See this Apple article: Change, add or remove Apple ID payment methods
https://support.apple.com/en-gb/HT201266
You are right. If you do not have enough storage space on iCloud, then you cannot backup your iPhone to iCloud. As you know, you will have to purchase a higher iCloud capacity subscription.
You have discovered that you need a valid credit/debit card listed in the payment method as well.
Axel F.
Don’t have credit card for more storage