From the note in your screenshot, the most common reasons are:

• You have WooCommerce, Polylang, or WPML active
• “Disable Ajax” is enabled
• Or something in your setup conflicts with how Lay handles navigation/caching

I’d check these first:

• Go to Lay Options → make sure “Disable Ajax” is OFF
• Temporarily disable plugins like WooCommerce or multilingual plugins and see if it becomes clickable
• Clear any cache plugin you’re using (or disable it for testing)

Lay automatically disables Layout Cache when it detects incompatibilities, so the grey checkbox is basically a “blocked by config” signal.

Try isolating it by disabling plugins one by one, you’ll usually find the cause pretty quickly 👍