Why do WhatsApp notifications persist in Focus - Do Not Disturb mode on iPhone 14?

I have not made any changes to default settings on my iPhone. When I turn on Focus and choose Do Not Disturb, my settings say that under both "People" and "Apps", "None" are allowed. But when Do Not Disturb is on, WhatsApp notifications continue to ping, interrupting video calls and anything else I'm doing.

WhatsApp had no advice (they have an AI chatbot which only gave vague answers).

Apart from going into Notifications in Settings every time I want to make a call and turning off WhatsApp notifications completely, is there any way to get it to work with the Focus mode I have selected?

I am using an iPhone 14, iOS 18.4.1. WhatsApp is not showing any available updates in the App Store.

Would be so grateful for any help with this. I really want to be able to mute it when I make calls.

Thanks

[Re-Titled by Moderator]