"don't forget to wear your life jacket", said the guide.(use "remind")

I have to covert the above sentence into indirect speech.

1. The guide reminded him not to forget to wear his life jacket.

2. The guide reminded him to wear his life jacket.

I have added "him" after the word reminded, I don't why?

Which one (1 or 2) is correct?

Both are correct for me, although "reminded him not to forget" might seem a little redundant.
You were quite right when you added "him", we have to know who the guide reminded. Without it the sentence wouldn't have been correct.
I agree with Pieanne on the awkwardness of the first sentence.

The 2nd person 'you' of the direct speech converts to the 3rd person 'him/his' of the reported speech (reported by a third party). It's kind of like looking at a TV image of a TV image of a TV image.
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