current month hide and previous month only need to show three month in dax

[THENNA_41]

I have a table name called combine effective date ( custom table) 

created measure for 

combine effective date = DISTINCT((VALUES('Append1'[Effective Date])))

Effective date values come from Append1 table.

Append 1 Table Date 

combine effective date

i am using for combine date for column chart axis value 

i  am using for slicer append 1 week date  

WEEK = var a = DATE(2020,08,03)

var b = IF(DatePA[Week Date] = a,"Outbound GLOBAL",IF(DatePA[Week Date]<>BLANK(),"Outbound" & DatePA[Week Date]))

return b

DatePA = DISTINCT((VALUES('Append1'[Week Date])))//,VALUES('PA - E2PR'[Week Date])))

slicer looks like

my column chart looks like 

slicer i use for date week from 

'Append1'[Week Date]

column chart i used  

'Append1'[Effective Date]

if user select july  month slicer in column chart july should be hide also only  previous monthly visible april,may.june .

any idea .  thanks in advance 

[amitchandak]

@THENNA_41 , for that you need a slicer on independent date slicer

Need of an Independent Date Table:https://www.youtube.com/watch?v=44fGGmg9fHI