Ignored cancellation request

I am very disappointed in the service I have received from First Loyalty Plus. Employees are very quick to sign you up but it's near impossible to cancel membership. I have sent numerous emails to cancel my membership and have given 21 days notice as required and stipulated on their terms and conditions but it has not been cancelled and my emails are just being ignored. I have recently started chemotherapy treatment and because of this will not be able to make use of the membership, due to medical bills I also do not wish to spend unnecessary money on memberships I am not making use of. Please think twice when taking out a membership from First Loyalty Plus as not even a medical diagnoses seems to be efficient reason enough for them to respond to a cancellation.