Motor Warranty Extender Section not responding

I would like to complain about Hollard's Motor Warranty Extender Section. Basically I have email confirmation sent to them whereby I clearly indicate I want to downgrade the cover to another option. They have also responded back in acknowledgement of my email request to them. However, since then I have had no response from them. When I called their call centre I was told I am now unable to downgrade the option as I have passed the cut off period. This is extremely unfair as I had already given instruction to them within and well before the cut off period for the downgrade. I believe that they are at fault and did not honor my request to have the downgrade completed within time. Thanks Mathew