How to resolve 'Could not communicate with the server' error and start iCloud on iPhone?

Restart your equipment and/or sign in out and back in again, and try again. On a computer you can also try Safe Mode https://support.apple.com/guide/mac-help/start-up-your-mac-in-safe-mode-mh21245/12.0/mac/12.0

Choose your macOS version at the top.

If you can't connect or sign in to iCloud or your account, Apple has a list of things you can try in the support article: https://support.apple.com/HT203512

Is the iCloud server working? --> https://www.apple.com/support/systemstatus

If your device is managed by a school or organization you may need to sign in to the device with a school or work Apple Account. More in this article —> https://support.apple.com/122725

If you are using a VPN try removing it completely (don't just turn it off) and see if you can then use the service. E.g., https://discussions.apple.com/thread/254836813?answerId=259008052022#259008052022

If using cellular data (even if it is seemingly good), try using WiFi instead. —> https://support.apple.com/HT202639

If you are trying to use a service from outside your Home Country it may not be available. From: Apple Media Services Terms and Conditions - http://www.apple.com/legal/internet-services/itunes/us/terms.html

- A. ”Our Services are available for your use in your country of residence (“Home Country”).

And: "Certain Services and Content available to you in your Home Country may not be available to you when traveling outside of your Home Country."

If an item is greyed out or restricted, see this support article —> https://support.apple.com/HT208982

For more assistance try the iCloud Support web site --> https://support.apple.com/icloud

If you still have problems try official Apple Support. Click here --> https://support.apple.com/choose-country-region Select your country, then a product. If you don't see one that handles your issue then keep experimenting with selections until you reach one that gets you a chat session or a telephone call and get the representative to redirect you.

or:

Contact Apple for support and service --> "See a list of Apple phone numbers around the world."

Click here --> https://support.apple.com/HT201232