Give up using a sealer. In a few years you'll be back to a nasty looking mess, again. Restoration is going to be a lot of work and mess. Use a good finish remover and carefully rinse with a pressure washer. Surface should free of old pigment and water should soak in when wood is wetted. It is very important to get the old finish off the deck or risk a blotching looking finish (may be more or less unnoticeable depending on old and new color or water beading after rain or rinse). Let the wood dry out a good week (a couple days in hot dry low humidity weather). Then use a penetrating finish (like Penefin Ultra). The nice thing about a penetrating finish is the maintenance. In couple years it will be time to do it again. Only this time you won't have to do the nasty aggravating frustrating stripping. Wash the deck (or lightly pressure wash) to remove surface dirt and then apply the penetrating finish. Do that every couple of years. A common mistake people make with a deck finish is thinking that a sealer will be low to no maintenance.