Fix 60K GMC Feed Disapprovals

I run a Shopify store that pushes about 60,000 SKUs into Google Merchant Center through the Simprosys Feed app, and a large share of the catalog is currently disapproved. Google keeps flagging data-quality problems, particularly missing or invalid GTINs/MPNs and related attribute errors.

Your task is to dig into Simprosys, audit every field that Google checks, correct the identifiers, polish the feed structure, and resubmit until the products go live again. Along the way, please fine-tune attribute mapping, shipping and tax settings, and any custom rules so future syncs stay clean. I’m only interested in someone who has hands-on experience rescuing large feeds like this, so highlight concrete examples of similar fixes you’ve handled when you reply.

Deliverables
• Updated Simprosys configuration and/or supplemental feeds that resolve the current disapprovals
• A clean Merchant Center diagnostics panel showing the catalog approved or within accepted error thresholds
• A short hand-off document outlining the changes made and steps I should follow to maintain feed health

Once everything is green inside GMC, the project is complete.