Claim not paid

A car insurance claim for my late mother since November 2021, claim number *** i have been sending in documents and been transferred to many different departments up until they sent me an agreement of loss and was signed and sent back after numerous calls i was told they wont pay until they get dicuments from courier company which were fetched early January 2022 and i have left many emails to check if they received the documents but there's no response, i then opted for phone calls everytime they always take my number and promise to call me back but nothing.