The answer to 'why is my faucet overflowing' is that there is likely a clog or blockage in the drain pipe or sink. This can cause the water to back up and overflow out of the faucet. Common causes include hair, soap scum, or other debris buildup in the drain.
Symptoms of an overflowing faucet include water spilling out of the faucet, a gurgling sound, or the water level in the sink rising instead of draining properly. To fix this, you'll need to clear the clog by using a plunger, drain snake, or other drain cleaning tool. If the clog is severe or you're unable to clear it yourself, it's best to call a professional plumber to diagnose and resolve the issue.