When 3G is enabled, I can't place/receive long-distance on my IPhone 4

[Andrewf]

Very frustrated with Fido, many phone calls, hours on hold, and no answers.
When I dial a call which has a prefix of "1" (long distance), I get an immediate two beeps and the phone returns to the dial screen. People calling me from long distance can sometimes reach me but most often not.
The problem is not the phone because I now have a brand new iPhone and the problem started before I got it.
Funny thing is, if I turn off "3G" , the calls will go through!

Any thoughts anyone?
Andrew

***Edited to add labels***

[justinreid]

I'm having this same issue on my iPhone 4S. I can't disable 3G specifically on the 4S, but disabling cellular data doesn't fix the issue.

[FidoStephen]

Hey Andrewf,

Sorry to hear about this. I must say, it's the first time I've heard of such an issue.

Do you happen to know if your SIM card is 3G? One way to tell is to take out the SIM and if it is 3G, it will begin with 8930237020. 

Was your previous phone an iPhone? What have you tried yourself?

Let me know, and I'll try my best to help you out.