Brown spot

[Islandguy]

Partly wool rug that has a large brown spot. When it is wet it does not show but as soon as I dry it returns . I dry with fan and dehu. I have tried acid rinse with no positive result .

 

[cleanking]

Partly wool rug that has a large brown spot. When it is wet it does not show but as soon as I dry it returns . I dry with fan and dehu. I have tried acid rinse with no positive result .

Can you share some photos of the spot/rug?