About the only thing you might want to try is to verify that the
drain's open. You can do this easily if you have a wet-vac. Just
pull the drain hose off under the sink, whether it's into a tailpiece
or disposal (or the air gap if one's used), connect the vac to the
drain hose and run it briefly. That will usually clear any drain clogs.
Beyond that, I'd probably suggest you call in a pro.
Hope that's of some help.
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