Hi, I created a product with 15 combinations each of them have impact on price, then I upgraded my shop to the latest 1.7.5 and I found in my front shop the product still there with all combinations and correct prices, but in the admin dashboard they just disappeared, I tried to rollback to 1.7.4.4 they appeared then upgraded again to 1.7.5 and they disappeared again, now I am afraid to continue using prestashop without solving this other wise I might lose similar data with future upgrades.. any solutions?
PS1: I use the default theme