If your Hard Head isn’t looking quite right or is seeming thicker than it should, then try thinning it using either Loon WB Thinner or a mix of 50% water/50% isopropyl alcohol. This method will likely work if the Hard Head is just a little thicker than it should be. If it has completely separated and/or seems really gummy, then you will likely need to replace it.
Shop Hard Head -- https://loonoutdoors.com/products/hard-head
Shop WB Thinner -- https://loonoutdoors.com/products/water-based-thinner