Open Settings
Tap Phone
Tap Call Blocking & Identification
Turn off any spam blocker or call filtering app listed there
If you use a carrier spam filter, open the carrier’s app and disable spam blocking
If you use a third-party call blocker app, open the app and turn off blocking features
Go back to Settings
Tap Messages
Tap Unknown & Spam
Turn off Filter Unknown Senders if needed
Check Settings
Tap FaceTime
Turn off any blocking or filtering options if enabled
Restart your iPhone if changes do not take effect immediately