norton 360 wont install on big sur

I Installed Big Sur as part of the beta programme. I noticed that my Norton Antivirus kept complaining that I need to install new virus definitions although they were up to date. Following advice on the Norton Website it requested me to remove the Antivirus and reinstall. since doing this I cannot install Norton Antivirus , I have spoken to Norton who of course helped but quickly identified that I was on Big Sur Beta and could not assist me any further

Any advice on how do I resolve this or revert back to an earlier build which may not have this problem. Currently I have no antivirus running on my desktop

Thanks in advance

Chris