Hi @TopMalinG ,

This issue can occur if your Project Planned Finish Date (and Activity End Date) is a larger date than your Calendar End Date. Therefore, you need to check project Planned Finish Date, Activity End Date and Calendar End Date in this environment. Both Activity End Date and Project Planned Finish Date should have back dates than your Calendar End Date. 

Source: 

Hope this helps.

Kind regards,
Dinushi

@Dinushi Liyanage 

Thanks you for the reply. Found the issue.

Regards,

Malinda

@TopMalinG  how did you find your issue? 

i have verified all our dates are within range and the generated calendar has those days in there as working days. 

Hi @ghaschke,

In my case, activity finish date wasn't within the calendar period. Once it changed, issue was resolved. 

Regards,

MalinG