Ports used by the game:
UDP: 3658 to 3667, 6000, 6010, 7000
Ports used by PSN:
TCP: 80, 443, 3478, 3479, 3480
UDP: 3478, 3479
Here is the list of steps you can try:
Start by testing your network connection. If the test shows that your connection is limited, try the following 4 steps to improve the connection.
1. Reset your network hardware
2. Forward ports
3. Place the console into the DMZ
4. Check for external restrictions
If you continue to have trouble after trying these steps, please feel free to contact us!