'System Data taking up ~90% of new phone space

There seem to be multiple threads on the same issue - and I have tried every suggested solution out there - yet the problem in unsolved. 'Systems Data' (for some people or previous ios I beliee this was 'Others') taking ~230 GB/256 gb . Aready running ios 15.6. I'm seriously distressed now - this is a new phone and I failed data transfer uncountable times - until I finally hit the underlying issue - this 'systems data/ others' space. Already spent unlimited nighs over this last whole month and my new phone (iphone 13) remains practically unusable. Any fresh tips ? Please help . I'm totally at my wits end.

'System Data taking up ~90% of new phone space
 
 
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