Bard Mez Question

[Nune]

So the other day when we had the mini PvP events (EC + Arena) I was runnin with some people in EC raising hell when I noticed something that kept happening when mezzing: nothing. It was casting on people, and not giving a resist msg but it wasn't mezzing. I thought maybe they were DoT'd or taking some damage to break it, but I was trying it on someone near me with 0 buffs and 0 negative effects. So am I missing something? I'll be the first to tell you I'm rusty on playing the Bard class in general aside from on a Blue server, but I remembered Bard mez working differently against me when I was on TZ.