Launching Teams App on a MAC

I have two Microsoft account, one is personal and the other is for my work (institution). I need to create new meetings for my classes using the institution account. However, when I start a video from it, it opens shows that it's changing user, and quickly the window opens up my personal Teams account. I cant teach with the personal account since my students are not connected to it. My students are in the institutional account by use of their university emails. Do I permanently close the personal account? I dont want to. Please help.