Minecraft PS3 turned back to trial mode?

I've had the full version of Minecraft for my PS3 for about 3 years. Then, this morning, when my cousin was playing, it somewhat put Minecraft back into the trial version. The game won't let us access our worlds, and we can only play the tutorial. Every time we try to get the full game, it says "An Ethernet cable is no connected."
We haven't been able to figure out what to do.