Were you able to see the bends or joints. That is where there is usually hair and other scum. You probably do have an obstrustion and need to snake it. You'll be amazed how fowl it can get
. Liquid clog openers won't work with certain clogs. It depends on how far away the clog is and how much matter has accumulated.
Also, I am assuming that the drain use to flow normal. Maybe someone else has an idea.
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