Can't call method that accepts Int16 value as argument

[Senadtm87]

As mentioned in the title I am having trouble with passing int16 argument while calling clrCall method.
When I call clrGetMemberSignature I get this: "Method: UnitOperation GetUnitOperationById, Int16",
after calling clrCall i get the exception " Could not find a suitable instance method GetUnitOperationById on type xxx for method parameters Int32[]".
Any ideas how I can call this without changing Method signature?