Unsatisfactory explanation

My mum is 61, she was asked to complete forms and send to Momentum. She was not sure of what was required and submitted these forms. My mum is on state pension, lives on her own and Momentum has changes her premium from R305 to R638, how does she survive with the rest of her bills, water electricity, rates, groceries, if you suddenly decide to double the premium? Have some compassion, as she initially was told the premium on Ingwe would be R305. It is also very ********* in the way you conduct business, has nobody bothered to inform the consumer of this change.