iStore Insurance is terrible

I insured an Apple iPhone 13 Pro with Insure by iStore after buying from them. A few days ago (19th Dec 2024) I submitted a claim for the ******/lost phone and their systems refused to submit I then sent them an email with my details and I still haven't received any feedback. iStore advised that I phone them directly and the agent told me that they would call me back but still haven't called me back?! This is so inconvenient!!!