No accept buttons in teams invite meeting

Hello, I have a complaint that some of the attendees of the meeting have got just regular emails without

"Accept" and "Reject" buttons.

At the same time, the button Join Microsoft Teams Meeting with the hyperlink, all of the details and everything persists in the meeting. How can I troubleshoot this?

The version of Outlook client is 2004 C2R 12730.

Some of the attendants reported they have a normal meeting request and they were able to accept it as usual.