Good afternoon,
What does the following different call disconnection reasons imply, and how do I go about fixing/troubleshooting the cause of the disconnection reason
Interworking, unspecified (Disconnect cause code 7F)
Call rejected(Disconnect cause code 15)
Service or option not implemented(Call disconnect code 4F)
Network(WAN) out of order(Disconnect cause code 26)
Invalid Call Reference (Disconnect cause code 51)