The problem you are experiencing is likely related to the kind of connection you are using to join an online game. There are three main NAT types: Open, Moderate, and Strict with Microsoft. Moderate and Strict NAT types limit the connections your gaming console can make to other gaming consoles. Ultimately, an Open NAT will provide the best connection quality. 


To find out your Xbox One NAT type "My Games & apps" > "Settings" > "Network" > "Set up wireless network" > (choose your network) > Once you're connected, you will be returned to the "Network settings" > "Current Network Status".


If you find you do have a favorable NAT type but are still having issues, try the following:


Step 1: Check the Xbox Live Status.

Step 2: Improve your home network quality

- The quality of a home network will have the biggest impact on game connection. We suggest the following tips to help improve your home network connection. Be sure to test your connection again after attempting each one; you may not need to perform all of these.

- Be sure to restart your router. This will often solve the issue.

- Try playing the game using a wired Ethernet connection. Playing a game using a wireless connection could lead to more lag and connectivity issues. Wi-Fi has a wide variance in reliability and bandwidth, and can dramatically affect the quality of online gameplay. A wired connection will maintain the minimum bandwidth connection that is required for online gaming.

- Disable any firewall or security features on your router. See your router’s instruction manual or visit the router manufacturer’s website for more details.

- Enable Universal Plug and Play (UPnP) on your router. This will automatically route the correct data to the correct ports.

- These steps are only for Sniper Elite 3: Set port forwarding on your router to the IP address of your Xbox One. Sniper Elite 3 uses the following ports: TCP Ports 53, 80, 3074 - UDP Ports 53, 88, 500, 3074, 3544, 4500 (You can use this link to help you with forwarding ports or you can contact your ISP)

- Place the IP address of your Xbox One into the DMZ of your router.