I've never seen a phone show that exact message, but to me, it sounds to be this phone model's alternate wording for "network busy". Network busy isn't something you can fix yourself and you're at the mercy of your carrier who needs to add capacity.
I have gotten this message on Telus (before moving to Public Mobile). It is very common for me to get this message on Telus and before that I used to get it on Fido. 5pm on Weekday near don mills and eglinton in GTA. Cell towers are overloaded and there is no capacity to handle additional call. After retrying the number couple of times the call does gets connected. It is network issue. The cell tower in the area has reached capacity.
I was calling the number for VMedia (company I have my TV and Internet with). My guess is that too many other people were trying to call them at the same time. I'm trying to think back a month....If I got through I was getting a message that all their agents are busy. and to call back later. I'd call back and maybe get the message "call limit reached". I'd keep trying and sometimes I'd get one message and the other times I'd get the other message. At the time I was thinking that the "call limit reached" message was a Public Mobile Message. It now makes more sense that it was probably coming from the VMedia phone system.
This happened about a month ago and hasn't happened since. I was calling from Mississauga to a company in Vancouver. I only got this message on maybe 50% of the attempts. Seeing as this seems to be an unknown message, I'm now thinking that the message wasn't coming from Public Mobile, but rather the called party end.
