Probable Resolution: Drain the tank and Check out the seal around the flapper. It may need to be cleaned to make a greater seal. If that does not halt the challenge, the flapper might be deteriorated and will need to get replaced. Verywell Wellness's content is for informational and educational https://credopost.com/the-importance-of-hiring-professional-plumbers-for-plumbing-and-septic-services/