my mum is 75 years old she received a letter from a company offering to buy her shares in another company for $7.50 per share. She was told if she accepted the offer within 14 days they would pay $8.50 per share. The existing price of her shares were $14 but my mum never kept an eye on what was going on. Mistakenly she signed the offer to sell her shares at $8.50. Now she has realised the actual value of the shares and cannot remember if the current price was stated on the letter of offer or not. Does my mum have any rights?