Our bathroom sink has been stopped up for days. After trying drain cleaners, I tried a hand auger. I removed the sink and all pipes (p-trap, etc) from the wall. I put the auger into the pipe in the wall and was only able to get it to go in about 3 feet. The only thing that comes out of the pipe is black sludge (it resembles tar) after trying for hours to get the auger to go in further, I gave up. The pipe still will not drain. Does anyone know what this sludge could be and what possible reason there would be for not being able to get the auger in any further? All info would be appreciated. Thanks