I just had a similar problem. I went to sleep with my product priced at $19.99 with a compare at price of $39.99. This morning I woke up to my product having been sold at $14.34. I never changed the price of my product and have no idea how it discounted the price of the product on it's own. I'm thinking there is maybe a glitch or something between Shopify and Oberlo product importer or something I'm just not aware of, but it is scary that the price of the product can just change own it's own.