Howdy maryettadesigns,
Thanks for participating in the Apple Support Communities.
Let's confirm that the email you're receiving is a legitimate email to rule out the possibility of this being a phishing attempt. For assistance with determining this, check out the following resource: Identify legitimate emails from the App Store or iTunes Store - Apple Support
If you determine this is a legitimate email, use the steps of the next resource for assistance with updating your payment method: Change, add, or remove Apple ID payment methods - Apple Support
Lastly, you'll want to Contact Apple Support if you're still seeing that you're being requested to update your payment information. They'll be able to check into this with you in more detail.
Have a great day!