Teamviewer 13 reconnected after support session was closed

Yesterday, a friend (John) asked me to help with a computer problem. I clicked (I thought) on his ID to connect. But I accidentally clicked on the ID of a different friend (Mary). I had helped Mary with a problem on her computer 1/2 hr earlier and then closed the TV support session when we were done. So I was VERY surprised when TV reconnected me to Mary's computer (without getting a new password from her)! How is that possible? It auto-filled and used used the same password Mary's computer generated earlier in the day. I thought that TV required a new password for each support session. I am running the latest version of TV13. Thoughts/Suggestions???