They dont care about their clients

I sent numerous emails and whats app messages to terminate my policy, but received no response. I called and was told to speak to their retentions department, but several times I held on for 40 minutes and no one picked up the call. I eventually got to speak with someone who cancelled my policy, but they still debited me for March and April, when I sent them mails in February, requesting cancellation. I want my premiums refunded for March and April. This is the least they can do after the shocking service and ignoring me as a client.