NIKWAX TECH WASH
TECH WASH: Your waterproof clothing and equipment could be soaking up water because the Durable Water Repellency (DWR) has been compromised by dirt, or because it has been cleaned with a conventional laundry detergent. Dirt attracts water and household detergents leave water attracting (hydrophilic) residues, leading to fabric 'wetting out' in wet or damp conditions.
If your waterproof clothing or equipment is relatively new, or recently treated with a Nikwax waterproofer, then cleaning with Nikwax Tech Wash® will not only remove contaminants, such as dirt and residues left behind by household detergents, but also revitalise DWR. https://www.nikwax.com/en-gb/products/productdetail.php?productid=4&itemid=-1&fabricid=-1