date type not showing hierarchy

[IraWatt]

My field 'Month of Year' is a date type but does not show hierarchy like my other dates.

Other field with hierarchy:

[IraWatt · Accepted solution]

I notice you can create the hierarchy by right clicking then slecting create but I'm still not sure why the little calandar icon is not apearing next to the fields name? 

[IraWatt · Accepted solution]

I notice you can create the hierarchy by right clicking then slecting create but I'm still not sure why the little calandar icon is not apearing next to the fields name? 

[IraWatt · Accepted solution]

The calander isnt there due to that field having a relationship with anouther table. 

https://community.powerbi.com/t5/Desktop/Date-Hierarchy-falls-to-appear-when-joining-on-the-date/td-...