If you find a problem, document it before making changes

If you discover an undisclosed problem, avoid immediately making repairs or modifications that could make the received condition harder to reconstruct.

First:

• photograph or record the problem where possible;
• note the steps required to reproduce it;
• compare it with the listing description;
• contact the seller clearly;
• check any applicable platform, payment-provider or carrier procedure.

A problem may also result from configuration, cables, power or compatibility, so rule out simple causes without unnecessarily altering the item.

The goal is to preserve a verifiable description of the condition as received before deciding how to resolve it.