The answer to 'septic tank not working' is that there could be several common causes, including a clogged drain field, a full septic tank, or a problem with the septic system's components. Symptoms may include slow draining sinks and toilets, sewage backup, or unpleasant odors around the septic system.
In many cases, the solution may involve having the septic tank pumped by a professional, repairing or replacing the drain field, or addressing other issues with the septic system. However, it's important to diagnose the specific problem before attempting any repairs, as improper DIY work could lead to more serious issues.