Is this the error you received?
7828: The part-name to the right of a part-ref with nonzero rank has the ALLOCATABLE attribute (6.1.2).
What does your code look like; without that, it's all just wild guesses.
That is the error that I am getting. The actual application is proprietary. Have created code that does the same thing using different variable names and data, so that you can understand the problem.
Character(len=:), allocatable :: Name
Type (XYZ_TYPE), allocatable, dimension(:) :: XYZ
XYZ = (/XYZ_TYPE("Coupon",1), &
XYZ_TYPE("Mark Phillips",4), &
index = Find_string(isize,sName,xyz%Name)
The error is on the %Name in the call to find_string.
you pass xyz%name but xyz is an array so xyz%name is an array of allocatable strings which may or may not be allocated and in general will have variable lengths. I think it is saying you cannot pass that as an arg due to fortran language constraints