Failed to dial in...

Hello,

I joined called today using RC services. However, when I dialed in I got a busy tone. I tried a few more time however it still failed. A co-worker then tried using her cell phone but when she dial-in she got the busy tone it wasn't until she tried a second time where it went through. My IT believes that its something to do with RC services where it was only able to handle one dial in at a time. It was just there conclusion as this isn't their area of expertise. Anyone else having this issue as well?