Why would the pilot light but burner not coming on?

If the pilot light is lit but the burner is not igniting, it could be due to a few reasons. One possibility is a malfunctioning thermocouple, which may not be sending the proper signal to the gas valve to open. Another reason could be a clogged burner or gas line that is preventing gas from reaching the burner. Lastly, there might be an issue with the gas valve itself, which could be faulty or obstructed.