Default web control tooltip doesn't reappear after auto disappear

I'm using the default webcontrol tooltip to make that beige box appear to the user for some useful information. Nothing fancy. WebControl.ToolTip property basically.

I notice the following:

When I hover back and forth over the control, the tooltip will appear and disappear. Nothing is wrong here.

When I hover on the control and leave my mouse there, the tooltip will automatically disappear after like 10s. When I move my mouse away from the control and then hover back on it, the tooltip no longer appears. So basically, does anyone know how to make it to reappear?

Thanks,

 Jandler
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