Help with sip trunk Maximum Channels

I am trying to limit the inbound as well as the outbound but i just don’t get the little note that pops up on the mouse hover. I have tried to put the from-trunk-trunkname that is auto generated down in the box that says context= under user details and i still can receive more than the 1 call specified. I just need to know how to limit incoming and outgoing from the trunk to save on bandwidth. Someone started to talk about it here but the person didn’t need help with inbound. Outbound works fine, (stops after the 1 and says all circuits are busy) but inbound keeps coming in.