Why does blocking someone on iPhone block WhatsApp calls?

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Here's how WhatsApp handles contacts and blocking on iOS:

1. WhatsApp Uses iOS Contacts – ✅ True:
   1. WhatsApp accesses and syncs contacts from the iOS Contacts app to show which of your saved contacts are on WhatsApp.
2. Blocking a Contact for Calls in iOS Also Blocks Them on WhatsApp Calls – ❌ False
   1. Blocking a contact in iOS settings (Phone or FaceTime) does not automatically block them on WhatsApp. WhatsApp has a blocking system, and you must block the contact separately within the WhatsApp app.
3. Text & Call Blocking Needs to Be Done Separately in WhatsApp Privacy Settings – ✅ True
   1. If you want to block someone from texting you on WhatsApp, you must go to WhatsApp > Settings > Privacy > Blocked Contacts and add them there. Blocking them in iOS Messages (SMS) does not affect WhatsApp messages.

Conclusion:

Blocking in iOS and WhatsApp are separate. You must manually block someone within WhatsApp for both calls and texts, as iOS system blocking does not carry over to WhatsApp.