Data not displaying in visualization

Hello everyone,

I hope someone can help. I'm experiencing a strange issue where calculated column data is displaying in my tables but when I try to use it under the visualization tab - either a filter or in a chart - it doesn't display. For example, I've created a simple flag under table:

Name                            Ex-Employee Flag

Joe                                1

David                            0

However in visualization, if I try to filter a graphic to current employees only (ie 0), all I can see under basic filtering is:

Ex-Employee Flag

is All

Basic filter:

[unticked box] Select all

If I create a simple card graphic to total the flag, I also get [Blank].

I've tried everything from refreshing data, unlinking all my tables and even rebuilding the report from scratch. Nothing works! I'm wondering if this is a problem with the latest Power BI update and whether anyone else has experienced the problem? Any suggestions greatly appreciated!

Tiff