How do I remove white fog from canopy?

I just picked up a new - used Phoebus C and the canopy is not scratchd
but has a slight white fog that cannot be removed with traditional
cleaning, Does anyone know if a product is available that will remove
this white fog?

If anyone is wondering, this is the Phoebus C that was on W & W for
the last 3/4 of a year. I am very pleased with the glider and was in
even better condition than I thought it would be in. I plan on making
this Phoebus like new over the next few years and replacing the
canopy. But in the meantime I would like to remove the white fog for a
clearer view while soaring.

Blake S Miller