“Verification Required - tap continue and sign in to view billing information”........ tne “Continue” button does not exist!!! The Option is “OK“ ADVICE PLEASE

The message is confusing. Many have posted similar questions and I suggest you send feedback to Apple about it (I have). There is also no mention in any support documents what "verification" actually means. Feedback to: - http://www.apple.com/feedback/itunesapp.html

I am guessing it means they want you to verify your payment information is up to date.* See if this is what they want: Change or remove your payment information from your iTunes Store account (Apple ID) - https://support.apple.com/HT201266

and if it doesn't help then: iTunes [Store] Support - Use this form for assistance with account and billing, code redemption, or purchase questions - https://ssl.apple.com/emea/support/itunes/contact.html

* E.g., https://discussions.apple.com/thread/8311981?answerId=33131818022#33131818022

How can I update my billing? I also have difficulty with this in my applications

Thank you... updated billing and all is well again...

Much appreciated