The phone is on a PBX but is not programmed properly (see PBX/Timing Configuration Codes, p.9).
Your phone is on a PBX that doesn't provide a) a hang-up pulse and b) produces a re-order tone less than 30 seconds after hang-up. Consult the party responsible for maintaining your phone system.
If you need additional assistance, please email us at support@talkaphone.com or call 773-539-1100 and select Technical Support.