The lid slides off its hook

The lid slides off its hook

The hook is not right over the rolled rim, the hook is bent, or the lid has been knocked out of round by a fall (TVWBB, TVWBB, owner reports). Hang it again with the hook fully over the rim and look at the hook. A bent hook or a lid that no longer sits true: contact Weber, as the lid is a warranty part; owners have had replacement lids.