Cloning CAN delete your game!

I cloned a few times, then I went to the Eleite Four again to train.
After I beat them, it said:

SAVING DONT TURN OFF THE POWER

Then it saved and I went into the "Records Room".

After all the credits were done, I tried to contine, but it said my save data was corrupted.

Now I have to start Emerald all over again!

At least this time I can start off with a different starter (I was thinking maybe )

This has never been reported. Its been known to delete the pokemon being cloned, but not a whole game.

Are you sure you didn't turn it off when you were still saving? When you try to start it again, it'll say the save data is corrupted, and the previous save file will be loaded...

It just seems odd that it deleted the game after the E4, instead of after cloning...some fake cartridges have been known to do that though...

I didn't turn off my game.
I waited until all my Pokemon were shown in the hall of fame, then I watched all the credits (in there any way to skip them?).

After that my game restarted and it said my data was corrupted.

I did try turning it on again. it didn't work.

I odn't get it.........

i've done item and pokemon duplication hundreds of times (for EV training i.e. vitamins and rare candys) and beat the elite 4 almost as much and i have never had any problems.
although the same thing happened to my sapphire cartridge once but it seemed to b random since i had done nothing else and u can't clone in rs
well sorry ur luck really sucked, i know that if my emerald cartridge file would be lost i would flip, i have like 70 lv100 ev trained (with proper natures and movesets) on my emerald file and all my 28 shinies and rare pokes. (i.e lugia, deoxys etc.)

Bootleg copies of Emerald have been known to erase all data when you beat the E4.
Cloning can only delete the Pokemon being cloned if you do it wrong. (Which happened with my shiny Golbat.)

Is the color of your Emerald cartridge a translucent green? Or is it gray like most other GBA cartridges? If it's gray, it's fake. Pokemon gives the cartridges color so you know it's a legit game.

No, its green, I don't get why it would do that though. It makes me so mad.

I did by it off ebay.......

EBay is very questionable, so that may be your problem. But if you're sure that you don't get a bootleg game:

One word: GameStop.