[mothered]

of my TV which is broken, I said that the package got wet, and that I got the electricity

Based on the above, you should've told them that (for safety purposes), you disposed of the TV.

I told them a thousand times that I have to dispose of the TV, but they say I have to give it back.

You can't give what you don't have.

Have you explained this (common sense) equation to them?