Students signing into a meeting with me

I had some issues with Zoom about a week ago.  Those issues are solved....I now am having a problem with screen distortion (just my students, not me).  Also, if I start a new meeting as usual, I am sitting there waiting for them to enter the waiting room.  NOthing happens.  They get a message saying that I am on another meeting.  Not sure what to do!  Was working fine prior to last week.