New laptop...students can't join

.I just purchased a new laptop.  Installed zoom with no issues. I am a piano teacher and use Zoom for one-to-one lessons. Now when my students try to join the meeting, they are getting a message that there is already another meeting in progress. I do not get a notification that they are in the waiting room. I have had to start the lesson on my phone, and then switch to my laptop, which is a nuisance.  I have pored over all my settings but can't find a reason for this.  Any ideas would be welcome! Thank you.