How to pass the control of call to internal extension

Hello

This is my first topic I´m new in this world of asterisk PBX, so I have a doubt when I was to create my dialplan I define the inbound routes and outbound routes both when I call to my PBX the call comes well and my extension answer, so far so good the problem is when I try to transfer the call with my phone but my phone is analog and I have define my code in the features.conf, when I press the code nothing happens, but if I press the code from the external phone (pstn), the code It´s accepted.

My doubt is how to pass the control of call to my internal extension?

I hope can you help me, thanks.

Regards

What options are you passing to Dial?

I pass the options TH, this is my code

exten => _XXX,1,Dial(SIP/${EXTEN},15,TH)
same => n,Macro(voicemail)
same => n,Hangup()

Regards

You need to add lowercase “t” for the called party to be able to initiate a features.conf transfer. (For security reasons, you probably do not want uppercase T in contexts accessed from external lines.)