One man realized he’d been paying his neighbor’s electricity bill for 18 years.

Ken Wilson has lived alone in the same apartment complex since 2006, he’s also paid his neighbor’s electricity bill for possibly 18 years, according to ABC News.

While Wilson was trying to cut back usage on his electricity and monitor how many watts his appliances use, he noticed his bill was still high despite his efforts to cut costs.

“Even after I turned off my breakers, I kept going outside to check my meter to see if it was still running and it was still running,” Wilson said.

Wilson contacted Pacific Gas and Electric Company to check his meter and the company’s representative confirmed his suspicions were not unfounded.

PG&E released a statement saying Wilson had been paying the electricity bill for the apartment next to him “since potentially 2009,” three years after he had moved in. But Wilson said he’s had the same agreement with the company since 2006 and believed the mistake had been going on longer.

The gas and electric company said that it fixed Wilson’s meter so he’d now only be paying for his electric usage and also said that the company credited over $600 to Wilson’s account with PG&E.

Anyone can verify that their meter is correct by comparing the meter ID number on the electric panel to the one on their monthly bill.