Fax: Failed to initialize UDPTL

I am not able to complete a fax successfully. It worked the other night to the same phone number, but no dice today.

FreePBX 2.11.0.23
Asterisk 11.7.0

I see a log entry about failing to initialize UDPTL. I’ve uncommented the ports in udptl.conf and started amportal.

Any advice?

Anyone have any idea?