Hi,
In the settings of the menu item, you can select if you want to display all the prices or only one price or a range of prices on the listing.
But on the product page you only see the prices of the current variant. If the selected variant has only one price, it's normal that you only see the price of that variant.
If you want to see all the prices of all the variants, you can change the "characteristics display method" setting of the HikaShop configuration to "list". That way, the variants will display as a listing on the product page and you'll see the price for each one in the listing.