It's got to be something with your controller. If you haven't tried already, try unplugging it, making sure the control stick is straight, and plug it back in. Or it could be a stuck button like 36 suggested, or just broken like Geko said.

Hey guys I need some help recently I've just opened the door to crush's dungeon in spyro 2 and ever since that door opened my spyro has been walking backwards I've tried exiting the game and going into different worlds but he still walks backwards any idea on how to fix this?

this is a strange suggestion, but try getting something (a fingernail works best) and scraping a bit underneath the edges around the L3 button. i don't know why, but i have the same problem as you, and i have to do that almost every time i use my PS2 nowadays.

Hey guys I need some help recently I've just opened the door to crush's dungeon in spyro 2 and ever since that door opened my spyro has been walking backwards I've tried exiting the game and going into different worlds but he still walks backwards any idea on how to fix this?

Does it do in other games too? Your gamepad could break, we have one here that always moves to the right x)