When my father died last year, nearly all the companies we had to notify were kind and empathetic, but not ScottishPower.

It had been paying feed-in tariff (Fit) payments for electricity produced from my parents’ solar panels into his account. My parents had bought the panels jointly in 2011, and my mother is named on the certification and was ScottishPower’s main point of contact, so she thought it would be a simple matter for the payments to be switched to her bank account. It was not.

Four months of nightmarish bureaucracy have so distressed my grieving 82-year-old mother that she is inclined to give up and let ScottishPower keep the money. She was required to complete three onerous forms proving she lived in her own home, and submit numerous documents including, insensitively, a copy of the will. These were promptly lost by ScottishPower.

She has since been bombarded by emails requesting information already sent and distressingly addressed to my late father.

Her own emails have been ignored and her complaints not acted on, and customer service agents seem unable to communicate with each other. Staff have shown no regard for her age and bereavement. It’s not an exaggeration to say that dealing with ScottishPower has broken her.

TM Cromer, Norfolk

You contacted me last September, a year after ScottishPower had sent a Fit payment to your late father’s account. By this point your mother was owed more than £1,000.

ScottishPower promptly apologised when I alerted its press office to her inexcusable ordeal. A spokesperson said: “We’re deeply sorry for the experience the family has had with us during such a distressing time. Our handling of the case is far below the standard we aim for, and we are investigating why this has happened and why it has taken so long to resolve.”

Did contrition resolve the nightmare? Not a bit of it. Another cheery email winged its way to your late father.

When you complained, ScottishPower finally twigged that you had lost a parent – it replied with condolences for the death of your mother.

Finally, in November, your mother received the year’s worth of Fit payments, without the interest payments you had demanded, and an offer of £75 in compensation, which you understandably considered derisory.

Two weeks later, an agent called your mother asking to speak to her late husband and, after being informed of his death, followed up with an email addressed to him.

“Does ScottishPower know what ‘dead’ means?” you asked in despair. “It means my father is no longer with us, he passed on, he has expired, he is bereft of life, he is deceased, he has shuffled off his mortal coil. It also means my father is no longer in a position to read emails or speak on the telephone.”

Another month went by. ScottishPower repeatedly promised that interest due on the late payments was being calculated, then suddenly announced that no interest was payable because your mother was to blame for delays it had previously apologised for. It upped its compensation offer to £150.

Last month, ScottishPower finally admitted it had wasted two months requesting unnecessary paperwork and had delayed processing paperwork that it did need. It also realised it had taken two months to act when it was notified of your father’s death last May.

It offered £300 in compensation, which includes the interest payments, and your mother has accepted this.

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