Calling from GSM gateway via outbound route?

I call succesfully from GSM gateway via sip extension which channel driver is chan_sip. But when i change it to chan_pjsip, so same extension can not call from GSM trunk. Even i can not hear any ring back from dialed number.
What can be reason?

I think you answered your own question.

May be I answered my own question but anyone can explain me how to solve this problem ?

… it stopped working. Switch back.

GSM gateway trunk can not be worked with chan_pjsip sip extension ??

Yours doesn’t seem to be able to. What technical reason do you have to using a channel driver that isn’t 100% ready for real-world use. It’s OK for phones, but there are people every week that are astounded that it doesn’t work in their particular edge case.

At some point in the distant future, it might work for this. As you have shown, that distant future is not now.