Overview

Amazon sellers who encounter Error 100333 are being blocked from adding or modifying product details on a suggested ASIN that they don't own or have permission to edit. This error typically surfaces during the listing creation process when Amazon's system recommends an existing ASIN as a match, but the seller attempts to change locked attributes on that product page. Understanding why this error occurs and how to resolve it can save sellers significant time and frustration when managing their catalog.

Key Points / What Sellers Need to Know

• Suggested ASINs have locked attributes — When Amazon suggests an ASIN match during listing creation, the core product details such as title, brand, and key identifiers are typically locked and cannot be modified by sellers who don't own the listing.
• Offer-only contributions are always allowed — Sellers can always create a seller offer (add themselves as a seller) on an existing ASIN without needing to edit any product details.
• New ASINs require a clean submission — If your product is genuinely different from the suggested match, you must remove the suggested ASIN entirely and follow the standard product creation workflow from scratch.
• Inventory file users need their process report — Sellers using bulk upload templates should locate the error ID from their inventory file process report, as this information is essential for troubleshooting and contacting support.
• Brand ownership affects editing rights — Only brand owners or sellers with explicit editing permissions can modify core product attributes on an existing ASIN.

Why This Error Occurs

Error 100333 is triggered under several specific circumstances during the listing process. Most commonly, it appears when a seller selects a suggested ASIN match but then tries to alter core product details like the title, brand name, product type, or product identifiers that are protected on that existing listing. The error also fires when inventory file templates include both a suggested ASIN reference and new product detail contributions that conflict with the existing listing's locked attributes. Amazon's catalog system is designed to maintain data quality, so it will block contributions that could create issues such as incompatible variations, incorrect categorization, or attributes that don't align with the existing product. In some cases, sellers may be trying to merge their product with an existing ASIN through the matching process, but their submitted information contains details that Amazon's catalog policies prohibit for that particular ASIN type or category.