Over a year and still no cylinders

In August 2021 I bought a gas hob and contacted Syd's Gas to recommend someone to install it for me as I was converting from electricity. A man by the name of Cassie Kemp gave me a quote and I asked him to do the job. On the 26th July 2021, Cassie duly installed it for me but when I paid him, I paid him for 2 19Kg gas bottles but he said he wasn't able to get 19kg so he "lent" me a 9kg until he could get my 2 cylinders. Periodically I contacted Cassie to find out where my cylinders were. He responded in different ways like, "I can't get them, I forgot and a few more". I got hold of Syd's gas earlier this year and spoke to Saul at Syd's and he said he would investigate and get back to me, well he didn't. I tried Cassie a few times more.....same stories. I contacted Saul again about 2 - 3 weeks ago and he told me that he'd get back to me after investigating and once again, I'm still waiting. Contacted Cassie again to be told, "I forgot" and he'd phone me back.....still no call. I find this poor service from both companies. All I want are my cylinders or for Cassie to come and fetch his cylinder and refund me the amount I gave him for my 2 cylinders but hey..... seems like I'm not getting it