How to use post function "Copy Value From Other Field"

[Artem Piskun]

I try to copy description field value from parent into sub-task description field by using post-function.
What could be the reason why I do not copy the value of these fields?

[Nic Brough -Adaptavist-]

You have not said what post-function this is, as in which app provides it - there are many on the marketplace that do this.

But my guess would be that you've misunderstood what the one you have chosen does.  Most "copy value" functions work on the current issue, copying a field from another one on the same issue, not poking data into other issues.