Trouble with nested if function

Hi
=IF(OR([@CATEGORY]="INCOME","N/A",IF([@CATEGORY]="PROFIT","N/A",IF([@ITEM]="MILEAGE",MAX(0,MIN(10000-SUM(I$5:I$5),I6,10000))*0.45+(I6-MAX(0,MIN(10000-SUM(I$5:I$5),I6,10000)))*0.36,""))))

I have the above which doesnt work I have pasted two arguments together, they both work independently as
=IF([@CATEGORY]="INCOME","N/A",IF([@CATEGORY]="PROFIT","N/A","")

and
MAX(0,MIN(10000-SUM(I$5:I$5),I6,10000))*0.45+(I6-MAX(0,MIN(10000-SUM(I$5:I$5),I6,10000)))*0.36,""))))

I have just added the OR to try and join them, can anyone advise?

Many thanks

Hi
Yes category is a column,I'm trying to avoid having to have column J (cost of miles)by adding the calculation into column s (costs paid)v2.3 MILEAGE CALC FOR FORUM.xlsx