Tap the icon (three vertical dots) in the top-right corner. Select Settings > Blocked numbers .
Look at carrier_blocked_timestamp in call_log . If this timestamp is after the user's unblock action, the carrier is overriding the OS. unblock contact android
Between step 3 and step 5, an incoming call can still be rejected because the telephony stack's mBlockedNumbers cache hasn't been invalidated. Typical window: 50-150ms . Tap the icon (three vertical dots) in the top-right corner