Attendees get a message that I'm in another Zoom mtg

This has happened numerous times. I copy the invite details and sent it to guests as anyone would. I then start the Zoom on my host account by or before the scheduled start time. Guests then tell me they are given the indication that host (me) is in another meeting! Which isn't true. It's as if Zoom changes the meeting credentials after I schedule the meeting. Typically I have no other meetings schedule so it's not an issue of my clicking on the wrong meeting.  Should I not select  "Allow participants to join at anytime"  when I scheduling meetings?