Often, when trying to tag people who are not involved in a thread -- for example, when trying to tag Liz or Amanda, I get "no matches." Sometimes if I keep trying, it will work, but a few minutes ago I was trying to tag both Amanda and Liz and was only able to tag Amanda. The system basically disavowed Liz's existence (bring her back!).
Is there a trick to this? I just begin typing the "@" symbol and the system searches and if the person is part of the thread, there are no issues -- but when the person is not part of the thread, many times all I get is "no matches."