Back to the Future Air Time Machine (Repair Required)

Thank you for looking.
We would appreciate it if someone who can repair it and use it would consider purchasing it.
A repair kit is also included, please refer to the photos.

It was used for about 5 months from the release date until April, within the home (by a 43kg woman), but it developed a hole and started leaking air. There is probably one hole somewhere. The air leaks a little overnight.

I tried to repair it, but I couldn't find the location of the hole, and I don't have the skills to fix it myself.
The box has some damage, but the air mattress itself is in like-new condition with almost no scratches or dirt, as it was used carefully with a mattress and sheets placed on top. Non-smoker. There is some sign of use within the normal range.

This is a DeLorean air mattress, a limited edition release from Don Quijote for the BTTF 40th anniversary. It is a single size but is large and sturdy. The air pump is electric. It makes a noise similar to a vacuum cleaner when inflating and deflating electrically.
Size: 190 x 100 x 46 cm