Can't purchase or download from apple store "iPhone"

Dears,

Suddenlty I couldn't update, donwload, purchase, or even re-installing the purchased app from my SAUDI APPLE STORE.

Whenever I click on donwload it shows that downloading process has began, but after 2sec it looks like cancelled.

I tried the below solutions but nothing changed:-

1. Close apple store from background.
2. Sign out from my apple ID and then sign in.
3. restarting my device.

Please support if you have any solution.