Date Connection (Power BI)

Hello! 

I'm new to Power BI. 

I have three tables:

1. Master List (my primary key here is the item reference number - RN).

2. Sold Items (this contains also the RN as Foreign Key)

3. Requested Items (this contains RN as Foreign Key)

I connect them all using the RN. 

Master list one-to-many Sold Items.

Master list one-to-many Requested Items.

Sold and Requested Item tables contain a date column. 

I created two visual line graphs with Y axis being the count of every RN sold and requested. X axis being the dates. 

I use the date of the Sold item in my slicer, but it only affects the sold graph. i used the requests date and it only affect the request graph. 

Then now i tried to create a calendar table dating from 01-01-2018 to 12-31-2024. I connect the dates from sold and request table to this new calendar table. 

Then I use the year from the calendar table, the slicer I get is with a (Blank). None of the year is working. if i click any of the year, the graphs (both of them) dont show anything. If i click blank, it shows all the whole period.  Please help!