PJSIP Transaction Error

I have an error:
res_pjsip/pjsip_distributor.c: Could not find matching INVITE transaction for CANCEL request
Do you know how I fixed it.

Don’t try to cancel a call you haven’t made!

What makes you think this message has any meaning other than its literal meaning, i.e. you issused CANCEL with a different call-iD and From tag from any current active INVITE.

It’s a protocol level error, there’s nothing for you to fix or change on the Asterisk side. We’ve gotten a CANCEL for something we don’t know of (or no longer know of).

Remember that the Call-ID header field acts as a unique identifier to group together a series of messages. It MUST be the same for all requests and responses sent by either UA in a dialog. As was said before , on the above posts . You are trying to cancel an inexistent SIP transaction