If the COA is missing essential data, the lab isn't accredited, or the product details don't match, that's a legitimate reason to complain. You're not being picky; you're protecting your business.

A valid complaint also applies when the report is technically correct but the product fails your market's safety thresholds. For example, if the heavy metal content exceeds your local limits, the report isn't wrong—but the product isn't compliant. That's when you should refuse the shipment and ask for a refund.

Always keep a copy of every COA for your records. You'll need them for audits, and they're your proof of due diligence if any issue comes up later.