Can not view products on front or back end. HTTP ERROR 500 - Resolved

-- url of the page with the problem -- : pumpkinvines.com/e/index.php/en-us/shop/...bamboo-blend-inserts
-- HikaShop version -- : 4.2.1
-- Joomla version -- : 3.9.11
-- PHP version -- : 7.1.22
-- Browser(s) name and version -- : Chrome
-- Error-message(debug-mod must be tuned on) -- : HTTP ERROR 500, debug mode on, error reporting set to maximum

I am not sure why but when I added a new product today the system seems to have gotten a bit messed up.
This morning everything was working fine.
At this time I can not access my products from the admin panel: Example
pumpkinvines.com/e/administrator/index.p...ikashop&ctrl=product

or from the front end.
This link works as expected: pumpkinvines.com/e/index.php/en-us/shop/diapers/kits
When I choose a product I get the Error 500: pumpkinvines.com/e/index.php/en-us/shop/...flour-sack-towel-set

I can see the products in categories - for example: pumpkinvines.com/e/index.php/en-us/shop/...value-pocket-diapers
When I click on the "choose options link" it doesn't go anywhere.

I went into the database and removed the product and it seems to be fine again!