Your Purchase Could Not Be Completed For assistance, contact iTunes Support at www.apple.com/support/itunes/ww/.

You should contact the official Apple Support directly about that. Only they can look into your personal data, to find the reason for this issue.

Use this link as a start:

Subscriptions and Billing - Apple Support

Or give them a call by selecting the phone number for your region from this Apple page:

Contact Apple for support and service - Apple Support

Sorry, but we are all users here, just like you, and we can not access your personal data. Only the official Apple Support dan do that.

Click on the blue links above to get in contact with them.

You're welcome 🙂

All the best!