1999 Volkswagen Beetle transmission fluid leak

It is a sealed trans. There is a plastic sealed tube that is on the drivers side front of the transmission just above and in front of the pan. You have to remove it to fill. Be careful not to break it. I has legs that grab inside to hold it on. You will also have to get a long hose and funnel to reach it through the drivers fender well. There is a drain plug in the pan. Allen head bolt. Drain it and put it back in. Then add 4Quarts of transmission fluid. No other way to check what is already in there.
Good Luck!