Are getting any specific error messages when you can't connect?
Here's a guide to Vita wireless networking that may help:
Greetings and thank you for the reply UJ. The wifi connected to my vita perfectly and the cpmmected test is successfull. It just happens to the game soul sacrifice when I try to play multiplayer. I get just network error without any specific error message. (Network Error!) I tried to browse around and it seems some players have the same problems too. It gives me network error especially when I try to connecting to a room. Even if I create room it will just kick me out after 10 seconds and give me same error.
Can you try connecting wirelessly to a couple of other networks rather than your home one? If you can connect to other networks without much issue that could point towards issues with how your home network is configured. If the connectivity is similar across the board the issue could be with the game ifself, or with the the vita either networking settings or maybe a hardware issue.
Can you play online correctly with any other games on your vita?
Everyone is having this issue now. It seems to be that Soul Sacrifice's servers weren't meant for this load.
My friend and I have been encountering this error in multiple locations and have other players disconnect from our game and come back blaming the network error message.
Same problem here mate and I also can't find a solution.
It's for a long time that these servers wont work and I'm really frustrated.
I can't even stay in an lobby in multiplayer! I get a Network error and the game brings me back to the game.
It's not our fault, like many are suggesting, it is the game's server fault.
I made a new topic, please (if you still have problems on the servers) respond on my topic, so that the playstation support will notice it and report it to the devs. http://community.us.playstation.com/t5/PlayStation