"Written Guarantee never Honored"

In 2010 I received my mothers inheritance a lot of money for me an invalid pensioner since 1972 and went to Canaccord genuity they bought shares for me and wrote a written guarantee on their value ie that as at end of 2013 theyd refund any loss on those shares The shares had by this time fell to close to nothing but theyve never honored the guarantee and I lost the lot.Can I add its not surprising they started to fall as soon as they bought them for me as I now know that their advisor was a seller of that stock personally immediatelly after I bought,,, a large holding too and he sold all of it that he held at Canaccord according to their managing director,so it appears he wanted me to buy a stock his own actions demonstrate he thought not much good,infact did he get me to buy in the hope id push the price up for him?Anyway canaccord nonetheless franticlt defended his behavior over and over again and remain adamant the guarantee not only will never be honored but that im immoral for even thinking it should be honored