Ridiculously Poor Service and claim rejection

Worst service received from any insurance company I've EVER worked with. I bought my house and insured it with SB Insurance 4 years ago. The house was expanded 30 years ago and thoroughly maintained. House was valuated by SBSA and insured. My boundry wall was blown over by a storm 2 months ago and claim logged online. SB Insurance initially rejected claim (while waiting for house plans to be submitted) saying the wall was not built to standard?? Weird that it was up to standard enough to be insured for enormous ammount. Also find out after 4 years (when I first and only claimed) that I've been paying for 4 years for 20% of my building s covered in THATCH (which was replaced by PREVIOUS owner 8 years ago! I have to phone twice a week, usually get cut off and NO one phones me back AS PROMISED on EVERY call I MAKE TO SBI. After two MONTHS I still have not received a rejection letter to take to court to pursue.. Dreadful Service. I've received nothing but GREAT service by SB Private Banking as well as Business banking where I've been a loyal client for YEARS now. Will not recommend and make point of pointing ANY future and current customers to basically ANY other insurance company