Nintendo 3ds xl after formatting pre-installed game gone?

Hi, maybe someone can answer the question.

Today I had formatted my 3DS XL because I wanted to sell it on ebay, Mario kart 7 was preinstalled, the guy who bought it from me said that Mario kart 7 was no longer on it. Can it be that Mario kart 7 was deleted by the formatting? Or is he lying?

I didn't know how to write it, thanks in advance.

Just download again

And how