Ms Stanley said her mum had not received any post from Aon.
“Her carers have regularly checked at the post office. She’s received letters about her state pension but nothing from Aon,” she said.
The 68-year-old said nobody from the company had apologised to her or her mother.
“They haven’t spoken to me in six months so I’m not expecting them to ring and apologise,” she said.
“It’s so frustrating, I came to the BBC for help because there didn’t seem to be anyone else who could help me. Things wouldn’t have progressed if I hadn’t.
“I worry that the same thing could be happening to other people. I’ve worked in finance for 40 years, so I knew what to do, but it’s been a difficult fight.”
A spokesperson for Aon said, after the BBC contacted them about Mrs Stanley’s case, that, after receiving some more information, they have reinstated her pension and the company had arranged for her to be paid the money she was owed.