Football bet settlement
What's the best way to document a wrong corners settlement?
Direct answer
Save the receipt and line, official event feed, timestamps of corners actually taken and bookmaker rules before filing a dispute.
How to use this answer
The principle is supported by the referenced rules, but a different operator or market can apply a different settlement condition. Treat the named provider as a specific example, not as a universal betting rule.
For player, card and corner markets, the exact selection type matters. A singles rule is not automatically the same as a bet-builder rule; use the market definition and the settlement source for the operator shown on your slip.