Netstar is *****ing my money

Netstar is de*****ing me by debiting money from my account , I have never signed a contract with them, they had a Year contract with the dealer I bought a car from , I received an email from them, informing me that the contract they had with rha dealer has ended and I should tell them of I want to continue with them, by that time my car was involved in Accident and was beyond repairs, I told them that , only to find out that they have debited from my account, I called them, they promised to cancel and refund my money, they never did instead we've been exchanging emails them promising to cancel and refund next and sending me invoice next, I told them that iI Pumla Xosana never had a contract with them, I am so dissapointed on them, they have tarnish their reputation