1. First, remove both tanks. Making sure there is liquid in them, check to make sure the liquid is not leaking from either tank. Also check that the cap is securely on the clean solution tank.
2. If either tank or the cap leaks, it’ll likely need to be replaced. Click the links below to order replacements:
Collection tank: http://www.bissell.com/collection-tank-assembly2037204?productid=8350
Solution tank: http://www.bissell.com/clean-watersolution-tank-2037207?productid=8350
Cap & Insert: http://www.bissell.com/cap-and-insert-for-formula-tank-2036677?productid=8350
3. If the tanks don’t leak when removed from your replace them on the unit and test one more time.
4. If they still leak, please take your ProDry® to a technician. You can find your nearest BISSELL® Authorized Service Center by clicking http://www.bissell.com/support/product-support/service-centers or by calling 1-800-237-7691, available 24 hours a day.