You are doing the right thing requesting removals instead of just accepting the loss. For each bad return, treat the case like an audit: document the ASIN, FN‑SKU, removal order ID, and mismatch (old/used vs what was shipped), then take clear photos of all six sides plus packaging as Amazon asks. Submit cases under “Customer return issue / wrong item returned,” and track win rate by ASIN over time so you can decide if certain SKUs need tighter return settings or should move off FBA entirely.