There are a few reasons why your drain might be clogged. One possibility is that you have a build-up of soap scum, hair, or grease. These can form a clog that prevents water from flowing freely down the drain. Another possibility is that there is an object lodged in the drain, such as a toy or piece of jewelry. If this is the case, you’ll need to remove the object before the clog will clear up. Finally, clogs can also be caused by buildup in the sewer line. This is a more serious problem that will require professional help to fix. If you’re unsure of what’s causing your clogged drain, it’s best to call a drain repair professional for diagnosis and treatment.