help needed badly!! psx2 copy game?

[NlPsxCopy]

hello i have a question ?
im looking for the answer all day!
i buyed a dvd writer to day and i have a psx 2 console with mod chip + dvd region x cd i use dvd-r cd to make a back up of the game and yes i did look if the game was a cd-rom or a dvd-rom
but ok here it is :
i made a copy of gta4 the copy was ready and i tryed to let it play in my psx2 but for one reason i can't get my own back up to play ...
i have a few copyed games and they all work but now that i have a dvd writer and i copy my own games it isn't working plz help me with this !!
thx