Solved Only two line, third line busy? Yealink phone W60B

[Song]

Currently I'm using voip.ms as my sip provider. I don't think there is a liimt n channel or port I can use. But Currently I'm having issues only two call can make at the same time. The third call get a busy signal. I'm using Yealink W60B + 3 W56H. I have setup the W60B manaully as described on the how to and was able to set it up. To link the other 3 phone to the base all I did was press the link button on the base and on the phone just click on register and enter password 0000 and assign it to base1. So currently 3 handheld is linked with the W60B. I see extension on there as 101,102,103. I can make calls inbetween other with no problem. I also have a desktop Yearlink T46s phone with extension 104.
Here is my test call.
First. 1 outbound with T46s phone
Second. 1 outbound with W56H phone
Third. 1 boutbound with W56H phone 0 get busy signal.

Anothe example:
First. 1 outbound with the W56h phone
Second. 1 outbound with the W56h phone
Third. 1 outbound with the T46s phone.

So my theory is I only have two line . I have 4 license on this. Anyone know if my configuration is wrong? or how do I resolve this?

Thank you

 

[Song]

I'm getting this message on the third line outboud. failed, cause: Cause: 486 Busy Here/INVITE

 

[Song]

nvm. fixed.. called my provider and they do have a restriction on the number of outbound call to the same number 2 max. that explain it. thank you all.