scalar function with input option in graphical calculation views input parameter .

I have created scalar function names as Time_UDF which returns values based on input text .

for example

select "LAXSAHU"."emear-sp.laxsahu::TIME_UDF"('PREVIOUS_MONTH_NAME') from dummy;

will return "2020-Q4-M11(JUN)" .

Now I want to use above function in my HANA Graphical calculation view.

Previous_Month takes string as input , so I tried to map the option variable with constant value as below

and Further option has constant value like below

so the value of option variable which is "PREVIOUS_MONTH_NAME" should be consumed by my scalar function Previous_Month(Time_UDF).

but when validating I am getting below error

I have tried my best but didn't find anything to fix this .

I would appreciate if HANA Gurus will help me on this .