Having same with me on new server. Manual dialing working fine but all calls going in PDROP in auto dialing. I tried with all routing and with agent and remote agent. When customer answer phone immediately call getting disconnected. I tried with 3 different provider including Twiliio and SIP.us. Same result with all provider. My server hosted on AWS. No any internal and external firewall. IPtables is also disabled.
When I checked tcpdump got that server sending BYE after call getting answered.
Vicidial Version:- 2.14
Asterisk:- 11.20