Trying to process data extract from an RPA action, transform that data, and then save it to another variable in the RPA

Hello,

As the title says, I'm trying to extract data from a table using Appian RPA, and then apply some transformation to that data, and save it to a variable also in the RPA.

The data is being fetched correclty, and the transformation "tested independently" is also working, but when trying to combine them, it doesn't work, as no data is being written to the final variable.

Can anyone help me please?

Thank you in advance!