Hi Last week I configured the 3CX for one of our customers. Everything worked fine but now, when they open their iPhone, they keep getting timeout requests. 2/3 extensions fail, note that 1 extension (working) is an IP phone, the other 2 are iPhone apps. On the PBX I notcied following: SIP Server/Call Manager ID: 4101 Extension 01 is unregistered, removed contact: sip:firstname.lastname@example.org.XX.XX:51745;rinstance=0-ik1knvlreh8m6u4uffdhxfkjkwgfpluz;ob;inst="072FA6" 01/08/2018 9:11:59 AM SIP Server/Call Manager ID: 4101 Extension 01 is registered, contact: sip:email@example.com:51745;rinstance=0-ik1knvlreh8m6u4uffdhxfkjkwgfpluz;ob;inst="072FA6" This happens for both exentions (01 & 02). I tried to load their profiles on my Windows client but the issue is the same. It looks like a problem with stun? What service should I restart? At the moment their are reachable, but only at 1 device. Any ideas anyone? EDIT: When i open my VPN to the customer, all is fine. I guess it's a tunnel problem. Also I noticed that the IP is in RED on the dashboard but this is normal as Dynamic setting?