Cisco Call Drop Issue

We are using Cisco UC520 Router with two analog line, We need to use (0/1/0) for all outbound & Inbound calls. We want to Disable All outbound call from (0/1/1). We need Incoming call on 0/1/1, When anyone makes call on 08 9377 3097 (voice-port0/1/1) it should be diverted to 206 (ext.) and if anybody is unable to Pickup call on 206 within 15 sec. then the call is Automatically diverted to a Mobile from 08 9377 0540 (voice-port0/1/0) But when we try to pickup call on mobile, the call drops after talking for few minutes. We Just need to fix the Call drop issue. For any clarification I will be able to chat with you on Skype ## Deliverables 1) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No 3rd party components unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the worker's Worker Legal Agreement). ## Platform Cisco UC520 , VOIP