Problem with Syncing trophies and Cloud access.

For some time now, I can't sync up my trophies and can't access the cloud to get my saves. It's giving me the error code NW-31456-9. I looked it up and did the fixes to my internet settings. Playing online still works, except for one game but I'm already asking help for that. However, syncing up my trophies and the cloud is still not accessble. Is there a way to fix this? Help would be appreciated.