Authentication on BYE

Hello all,

I works with Asterisk 1.4.19.1 with FreePBX 2.4.0.

When I call, it’s works fine.
Sometimes, when I hangup a call, my phone ring again with the number of my last caller.

It seem that Asterisk don’t authenticate on BYE.

How can I fixe this “bug”?

Thanks

Best regards

Anthony