Doing a Calculation on DATE data from pulldata function

Dear all,

I have a form on which does a pull data of an external csv file. One of the fields pulled from an external file is a date column describing the last time a certain medical test was done.

I want to determine when the next test date should be by adding 365 days (1 year) to the date , see image below. However when I try to display the output in a note (nextHVL in the image below) this show as blank.

Does anyone know how I can manipulate dates pulled by pulldata from a csv file and adding days to them?

@Tumaini, the data pulled from a pulldata function gets stored as a string format. You will need to transform the data to a specific format to make calculations which I see you have already done (with dates). Could you also try with a number format to see if you are able to add or subtract?

@Kal_Lam do you mean transform date to a number? I am not sure I have understood you correctly

Is there any solution to this issue?

Greetings,
I have the same problem and I have tried to convert the data in date format obtained from pulldata with int() and number () as Kobotoolbox support points out, I have also tried using date() and it works perfect in Enketo environment but it does not show the values in KoboCollect. I have been trying for several days but I have not found the way and I need to solve it urgently.
In Enketo it works perfect
Here I have also addressed it Question