Circular Dependancy when creating Relationship

It's worth trying the folowing. When you create the relationship drag from the fact table (many side) into the date table. I think you'll find it works! I know I've had that issue before but now trying in latest version of Power BI I can't recreate the problem at all and it works both ways round.

However I tend to avoid using CALENDARAUTO and go for this sort of approach...

Date = 
    VAR EarliestYear = YEAR ( MIN ( Purchases[Date] ) )
    VAR LatestYear = YEAR ( MAX ( Purchases[Date] ) )

    RETURN
    
    ADDCOLUMNS (
        CALENDAR (
            DATE ( EarliestYear, 1, 1 ),
            DATE ( LatestYear, 12, 31 )
        ),
        "Month Year", DATE ( YEAR ( [Date] ), MONTH ( [Date] ), 1 ) //Format as mmm YYYY 
    )