App Store keeps telling me to verify my billing inf, I go to it, it’s fine, I go back and it says the same thing over and over. Won’t download apps at all

See If your payment method is declined in the App Store or iTunes Store https://support.apple.com/en-us/HT203005. If you need additional help, use this support link from the document https://support.apple.com/contact

But, also see these reads pertaining to a related error: 

Payment method declined in iTunes or the App Store ...

Fix 'Your Payment Method Was Declined' Error In App Store

Why do I keep getting a message that my Apple payment ...

Also, can get Apple telephone support  for help in solving your problem using this link https://getsupport.apple.com/?caller=kbase&PGF=PGF63005&category_id=SC0245&symptom_id=23362  Be patient sometimes Apple support is closed to immediate phone support.

or useApple Support Twitter https://twitter.com/AppleSupport

And here is how to contact iTunes worldwide support via text or chat using this link https://support.apple.com/choose-country-region/itunes After choosing your country, see the heading Tell us how we can help.

See if anything here helps.

How to Fix “Verification Required” for Apps Downloads on iPhone and iPad