Unclogging the drain...
 

The most clog issues are solved with a plunger or drain snake. Use such tools for unclogging the pit. Minor clogs can be removed using a plunger. You can hold a wet towel on one of the drains and plunge the other one. It will pull out the debris. Then repeat the same procedures over the other drain.
Once we had a drain clogging in the bathroom, our residential plumber asked us to pour a gallon of hot water into it else the mixture of baking soda and vinegar. And surprisingly it worked.