Grafana notification in the telegram group sometimes works sometimes doesn't work

Hi,
Using grafana v9.1.1 . For some reason, notification in the telegram group doesnt work. When I reconfigure the notification policies, alert comes to the group. After some time, the alerts stop coming to telegram again. Maybe someone know how its fixit? I can’t figure out what went wrong.

Set the message templates & contact points for 2 groups Telegram.

Install default contact point for one group, set up another group for matching labels .