Channels unavailable when make outgoing calls

Hi to all,
I’m a new bie of FreePBX and Asterisk, and I’m trying to setup my first VOIP system.
I have FreePBX with a PCI card TDM400P and 2 FXO channel connected to 2 analog phone lines. I configured the system with 3 GrandStream phone and 1 XLite softphone.
All works perfectly if I made internal call or receive call from the TDM interface, but I can make no external call from the SIP phone.
I configured an outbound route over the trunk Zap/g0 created by default from FreePBX but when I try to make an external call, I get always the voice saying the channel are all busy.
Where is the problem in your opinion?

Thank you very much for your help!!

Hi this is my problem now. How did you solve this?