What do I have to do to get Liberty Life to stop taking funds from my account?

What do I have to do to get Liberty Life to respond to my request and to stop taking funds from my account?

We have emigrated. I would like to discontinue a life insurance policy held with Liberty Life. I sent a request this effect and received the following response on the 30th of January:

"Thank you for your query and we will respond to you within 5 working days."

Today is the 23rd of February and I am still waiting for a response. Liberty will no doubt take the monthly premium from my account at the end of this month. What do I have to do to get Liberty to respond and to stop taking money from my account?

Please note that the telephone number I have entered is for the United Kingdom - I do not have a South African mobile number anymore.