British Town: Unresponsive, Uncooperative Course Cancellation Issue

I registered for the British Town Lara (Antalya) course via WhatsApp on October 7, 2023. For a 2+1 course, they told me a price of 25,800 TL. I notified them that I could begin on November 15, 2023, and there was no problem. They did, however, clarify that I needed to submit a partial payment in order to finish my registration. I paid a down payment of 5,800 TL on the same day (07.10.2023). Later, on October 14, 2023, I contacted to cancel the course, citing personal reasons, and was told by the assistant that the branch manager, Ms. B**, was in a meeting. Ms. B** finally called back after two days of no response, originally indicating that the cancellation was not feasible. I explained that I hadn't received any course materials and that the course wasn't for another month. She then emailed me a sample cancellation letter, which I swiftly completed and returned on October 17, 2023. However, no reaction, favorable or negative, has been received. Despite multiple calls and messages, I received a message on October 20, 2023, claiming that my letter had been submitted to the accounting department and that all processes were controlled by a single accounting department. I contacted and messaged again on October 26, 2013, to inquire about the procedure, but received no response until today (November 13, 2023). The officials, who were earlier eager to sell the course, have been completely unresponsive since I voiced my desire to cancel. Ms. B**, who spent hours explaining the course to me before I decided to purchase it, opted to stall when I wanted to cancel. They don't read my messages or return my phone calls. They exacerbate the problem by adding to it. Everything appears to be in order until they receive the money. Even now, they do not return my calls. If this problem is not remedied quickly, I shall take legal action.