Tax adjusted trading profit – legal fees incurred while leasing business premise

I really don’t understand why legal fees incurred to gain a grant to lease the business premises for n years is not an allowable deduction, so it must be added back to net profit?

Isnt it clearly a cost for business purposes?

Is it all legal fees thats not allowed? Because i remember during completing numerous similar questions there was legal fees and it was allowable i think?

Cant find it now though did too many of them.

If you could please clarify this that’d be great thank you very much