Message Oracle PLS-00667 - Element type of associative array should be pls_integer or binary_integer

ERRORElement type of associative array should be pls_integer or binary_integer
CAUSEAn attempt was made to specify index collection whos element type was not one of pls_integer or binary_integer.
ACTIONChange the index collection variable type to associative array whose element type is pls_integer or binary_integer.