Microsoft has added a new type of notifications in private chats in Microsoft Teams: urgent notifications. Basically when we are writing a message in a private chat we can categorize it as an urgent message. Marking a message as urgent means that the recipient will receive a notification every two minutes for 20 minutes unless he/she reads first the message.
An urgent message is visualized in the following way in Microsoft Teams:
And the recipient will receive the repeated notifications in the following way: