How to enable disappearing messages for specific chat in WhatsApp
Open the specific WhatsApp chat where you want to enable disappearing messages. Tap on the contact name or group name at the top of the chat screen. Now, tap on "Disappearing messages." Choose the desired duration for the messages to disappear: 24 hours, 7 days, 90 days, or "Off." Finally, tap "Turn on" to confirm the changes.