Okay so i had this problem as well... It says unable to connect to UGC servers... I found a solution! And believe it or not it's really simple!
-The inFAMOUS2 disc MUST
be in your PS3 during this process
-This method was discovered by me so plz credit me if you post this elsewhere on the forums...
-This is NOT THE ONLY
method but it is by far guaranteed and tbh it's much simpler and less time consuming than other methods
Now Follow these simple steps to get back to playing UGC missions
1st) Reboot your modem/router (switch off and back on) and wait for a few seconds till it reboots...
2nd) Go to the what's new option in the XMB cross media bar (it's located under account management) and then scroll down to the recently played row... Find inFAMOUS2 and press start! And voila!
That's all you need to do! Now was that so hard?
I've tried this method many times and it always works,It helped many of my PSN friends who had the same issue! I hope it helps you