Twitter could not be purchased at this time

Hello,
For a few days I have this kind of error from App Store. I cannot buy anything and I don’t know why. My account is not banned and I am a little bit confused. I have this error on my iPad only and the App Store is working great on my iPhone using the same account. Can anyone explain me please what is wrong with my iPad ?
Thank you experts !

Unable to Purchase
“Twitter” could not be purchased at this time. Please try again later.
OK
