"Copyright protection is Invalid"???

I copied one of the free PSP games (Pursuit Force), to my PSP and whenever I click to play it I get that error message. It makes no sense, I legally downloaded it from the oficial welcome back package but it won't play. Do I need to be signed in on my PSP? My wifi has been broken on my PSP for years so I never had a PSP account. Anybody else get this message?

I've gotten it. I think I fixed it by deleting the game and redowloading it.

In order for it to work, I have to sign on to my PSN account on my PSP while also being logged into my PSN account on my PS3. Then I connect my PSP to my PS3 and enter "USB mode." From here, I press X, and it'll ask if I want to copy. I confirm that I want to copy, then it has to activate (which requires you to be online). Once that's settled, it begins the copying process. From then on, I'm able to select the game from my memory card on my PSP and play. I can't simply copy the game to my PSP memory card and expect to play it.