The general settings for notifications on Telegram lets you customize the notifications for the entire chats and groups. But to disable notification for a specific chat or a group, you need to do as follows:
1. Open the Telegram on your Android device
2. Tap the chat/conversation/group you want to manage the notifications for
3. Tap the contact/group name on the top to open the details
4. Tap the Notifications and Sounds option
5. And there you can manage the notifications, including the vibration and sound
** To completely disable notifications, tap the Notification option, followed by the Disable.
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