Unable to make a purchase

hello, Iam having trouble purchasing an app from the App Store. When i log In it re-directed me to setting so i can change my card information, in which i did. Then Iam all set to make the purchase now and it tells me my purchase cannot be made please contact Apple support, doesn’t give me much information as to why i cannot Make the purchase and it most certainly has nothing to do with my card being declined because it was not. Can you please assist? Thank you!