No values when using key figure with constant selection?

Hi experts,

I have built a Webi on top of a universe that is sitting on top of a Bex query.

In my Bex query I have a bunch of key figures defined that are restricted on time and category.

This Webi works fine.

Then I added an additional key figure that required a constant selection on time and on category.

When I first added this to my Webi report it was fine. But once I refreshed my report showed no values.

The report still seems to know that it is meant to retrieve values because it is bringing back the correct records - just no values. (ie I am showing time in my columns and it's showing the correct periods that are meant to have data)

I refreshed a number of times and sometimes it would bring "#TOREFRESH" in some cells but once I refreshed again the cells are blank. Sometimes it would even show me a value in a couple of cells and others would show the "#TOREFRESH"

I went back to my Bex query and removed the key figure with constant selection and the report is working again?

Has anyone experienced something similar? Is there a way to make this work?

Thank you!

Sabine