“I would give this 5 stars if it wasn't for the fact that I got less skins than it said I would get. I was supposed to get 7 but I got 3.. I didn't pay $45 for that... but besides that the service that I was given was decent. I got a response by the end of the day which is better than never getting one. I only wish that the amount of skins said was the amount that I actually received.”
It looks like you actually just miscounted the skins. You need to go through and manually check each champion for skins. Your account came with a few skins that are no longer obtainable, so they won't appear in the store, even if you check the 'Owned Skins' tab.