Bought used copy of Ragnarok Odyssey .... need help

Ok, I bought a used copy of the game last night , got home popped it in my Vita and it says I cant get trophies because only the 1st user of an application can get them. It says if I want to get the trophies I have to delete all files of the application and restart the application. How do I do this? Originally I thougt it was because I downloaded the demo and it was reading that. Apparently it is on the game card itself because I see they got as far as world 2-8 . I hooked my Vita up to the PS3 but I cant access the game from there either. If I use the back up and restore option will that wipe the card clean? I played some today just because I wanted to but I would like to get the trophies and what not as well. 

Hold your finger over the game Icon and than delete it to remove the previous users saved trophy data. Here's more information in this thread.

http://psvitaforum.com/threads/psv-game-card-reset.8724/

^^^^^^

That was the answer, thank you !