Agility Insurance - ********* Practices

I cancelled my insurance with Agility in May 2018 (via an e-mail sent on their website, as I have paralysed vocal cords ) and then stopped the Debit Order from being deducted off my Bank a/c. In June, Agility changed the name of the Debit Order to Tracker Agility and still deducted the Debit order off my Bank A/c. I stopped the debit order on the Bank A/c again. Again, Agility changed the Debit Order name and this time deducted 13 months insure all at once. How can I stop this ********* practice and get my money back?