Gears For Ears review for QuickBooks Online

I installed this app with high hopes. I setup the app and tried to sync my shopify and quickbooks inventory according to the instructions given in this app. I spent a day fixing the names in both platforms. But when I finally synced it, I had duplicate of of my inventory in QBO. It is a big mess which I can't even solve. Quickbooks doesn't allow merging of two inventory items, nor can I delete my inventory. I followed their instructions VERY clearly and now am stuck with an irreversible problem. This is very very frustrating.