Hello
This is driving me nuts. I created a flow to create a task in planner when a list is updated (when a list or item is modified), this flow uses the "Create Task (preview)" and the task labels are populated based on a value from a column in my list. If the item is "Low Value" the label will be Pink, if the value is "BID-ITB" the label will be Red and so on.
In this flow I can define the label using the expresion: IF(EQUALS(variables('AppCategory'),'Low Value'),TRUE,FALSE) for Pink as custom value in the Flow and so on for other labels. And it works very well (see image).

But this same method (create a task "preview") is not working with a second flow that I created in the same environment. This flow is triggered when a task is completed and in the "Create Task" step I just need to update the label based on the value from the completed task but no matter what metthod I use to enter the custom value, those fields are deleted after saving my flow.
I have tested using Dymamic Content with the Pink, Red, etc valiables from "when a task is completed" trigger, also with the expression: not(empty(string(triggerOutputs()?['body/appliedCategories/category1']))) that evaluates as TRUE if the "when a task is completed" has the Pink label or category1, or red for category2, and so on. (as suggested by @MarvinBangert )
No matter what method I use for defining the task label, the content in that field is deleted after saving my flow. So I created another Plan to test if my power platform license is not allowing me to update tasks on 2 differents flows (which would be very weird) but I have the same result with another flow using a different plan (see images)

In both cases, the value in the labels are not saved in my Flow (deleted right away after saving the flow). And I'm out of ideas for solving this.

This is what I get right after saving my flow (really weird) all the values in the labels are gone.
Please help.