Cellphone insurance

I took a cellphone contract with Vodacom on the 20 of February 2020 and I insured the phone iPhone 6 on the same day. I asked the lady who was assisting me at Vodacom Store to put my old sim card into the phone and she did and did some settings on the phone. This year January on the 26 I lost the iPhone 6 I put a claim with Vodacom insurance but they decline it they stated that I was not using the sim card or the number the phone came it and the lady assisted me never told me and she was the one who put my old sim card in that phone. As far as I know I was insuring the phone not the number. My question was why they let me sign the insurance if knew I wouldn't be paid if I claim and i asked them to give me my money was paying because this was *******