What does the big red dot next to the clients phone number mean?

I have had several clients book with me and have the Big Green Dot next to their Rover phone number. These past two weeks or so, I have had two inquiries where it’s a Big Red Dot next to their phone number. One of the boarding requests seemed a little off to me, and another is a drop in request for this coming weekend. Both requests had no pictures and was a newly created profile. The drop in request does have care instructions and seems more legit. Just curious as to what the Green and Red Dots mean. Thank you!