Cannot Label a File with Azure Information Protection

Hi,

I am learning Azure Information Protection. I am following the quick tutorial at https://docs.microsoft.com/en-us/azure/information-protection/infoprotect-quick-start-tutorial .

In step 4, in the sub topic “To see a recommendation prompt for labeling and automatic protection” at https://docs.microsoft.com/en-us/azure/information-protection/infoprotect-tutorial-step4#to-see-a-recommendation-prompt-for-labeling-and-automatic-protection , when I try to click “Change Now” button, I will get an error message “Azure Information Protection cannot apply this label. If this problem persists, contact your administrator or help desk.”. I try many times and always get this error.

I follow all steps in the tutorial and all ones before this step are completed successfully. But this one always fails.

Please help.