Bad service on purpose

Impact informs me my account is extremely high. I stay in a complex my flat is Unit 39 Upon inspection the unit below me Unit 37. When he uses hot water it also ticks on Unit 39 hot water meter so I have been paying for both Units hot water. I spoke to people feom impact but they refuse to send someone to come fix their meters. Its alot easier for them to send invoices that are sky high than rather solve the problems. Are they going to reimburse me for their mistake propably not! This is called theft!