<p>As commented before, the t_set_no_e2e_cancel_reason(1) should be used when handling the INVITE.</p>

<p>In your case, you can use the workaround of removing the header and applying the changes, so it is no header to propagate.</p>

<p style="font-size:small;-webkit-text-size-adjust:none;color:#666;">—<br>Reply to this email directly or <a href="https://github.com/kamailio/kamailio/issues/261#issuecomment-125496535">view it on GitHub</a>.<img alt="" height="1" src="https://github.com/notifications/beacon/AF36ZQIv_3rB9bpTtwpXXw9SezBmkGOrks5ohzLrgaJpZM4FeeF3.gif" width="1" /></p>
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