Conversations involving multiple participants, allowing collaboration and information sharing in Teams
Since a month or two, I also can't make bulleted lists anymore in a Teams message. The first bullet is fine, but if I press Shift+Enter, the next line doesn't have a new bullet, and if I press Enter, it sends the message. No way to start a second bullet!
You need to put your text field into edit mode, and then you can hit enter to get more bullets (or numbers, etc.). To do that you can either do the keyboard cntl+shift+x or click the A/pencil icon.