Paying for cellphone insurance without a cellphone

In May 2016 I bought a Samsung J1 cellphone at Jet Wonderpark and took a cellphone insurance. The sales person wanted to give me a display which I DID NOT TAKE because that was the only phone left in the store. The phone was credited immediately and the cellphone insurance was cancelled accordingly to the sale person. To my surprise on the 13 April 2018 I learned that am still paying for that insurance of a phone I never took from the store. I went back to the store only to find that the lady who help me resigned but there was a lady who helped check if the who was credited back to my account and if the insurance was cancelled. The phone was credited she even showed me a slip but no evidence if the insurance being cancelled. She called the insurance and even send them an email with the copy of the slip. I called the store the following week was told they are still waiting for the response from the insurance. I went to store in May to check what's happening, was told the insurance only have 8 transaction from my account as proof that they have been paying for the phone after I played them for 24 months. The lady asked if I still have statements from May 2016 to date. Checked my emails and foturnately I still had all the statements which I forward to her and she did forward to the insurance. A week after I was told to come signed some papers at the store but on arrival I was I also told there's no need for that. After a 2 weeks I called the store to inquire about the progress, the lady who was helping was on leave then I asked for the supervisor where I had to explain the whole story to her. She promised to call the insurance and and call me back which never happened since I did not receive any call from her. After a weeks I called again the lady is still on leave then the supervisor says she did call the insurance but no one new about the story and she can't help cos the peson who was helping me is still on leave. I asked her to give me the number for the insurance, I called them without any lucky.