A botched water meter connection means a Devon woman has been charged for both her and her next door neighbour's water for nearly a year.
Mrs Symm found the fault when she carried out her own investigation
Beatrice Symm had a water meter fitted at her Okehampton bungalow last July and could not understand why her bills were so high.
She thought it would save money, but despite paying £28 a month, the debt on her account is now more than £400.
South West Water has apologised and promised to correct the reading.
They have disconnected the meter and will now charge Mrs Symm a rate based on average water use.
She said: "We're being asked for £380 a year and currently pay £28 over 10 months.
"We don't think we use that much anyway."
Mrs Symm only found the meter was also measuring next door's water after making her own investigation.