The answer to 'drain trap overflowing' is that a clogged or malfunctioning drain trap is the most common cause. The drain trap is the curved pipe under your sink that is designed to hold water and prevent sewer gases from entering your home. If the trap becomes clogged with debris or the water level drops, it can cause the drain to overflow.
Some common symptoms of a drain trap issue include water backing up in the sink, a foul odor coming from the drain, or water leaking from the trap itself. To fix this, you can try plunging or using a drain snake to clear the clog. If the trap is damaged, you may need to replace it. If the problem persists, it's best to call a professional plumber to diagnose and resolve the issue.