Help with Previous Month Metric

Anonymous , Join your date with date of date table and try to use time intelligence

examples

MTD Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESMTD('Date'[Date]))
last MTD Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESMTD(dateadd('Date'[Date],-1,MONTH)))
last month Sales = CALCULATE(SUM(Sales[Sales Amount]),previousmonth('Date'[Date]))
MTD Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESMTD('Date'[Date]))
last MTD Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESMTD(dateadd('Date'[Date],-1,MONTH)))
last month Sales = CALCULATE(SUM(Sales[Sales Amount]),previousmonth('Date'[Date]))

or

MTD =
var _max = if(isfiltered('Date'),MAX( 'Date'[Date]) , today())
var _min = eomonth(_max,-1)+1 ,
return
CALCULATE([net] ,DATESBETWEEN('Date'[Date],_min,_max))

MTD =
var _max = min(MAX( 'Date'[Date]) , MAXX(allselected('Table'), 'Table'[Sales Date]))
var _min = eomonth(_max,-1)+1 ,
return
CALCULATE([net] ,DATESBETWEEN('Date'[Date],_min,_max))

This Month =
var _max = eomonth(if(isfiltered('Date'),MAX( 'Date'[Date]) , today()),0)
var _min = eomonth(_max,-1)+1 ,
return
CALCULATE([net] ,DATESBETWEEN('Date'[Date],_min,_max))
eomonth(if(isfiltered('Date'),MAX( 'Date'[Date]) , Maxx(allselected(Sales), Sales[Date]),0)

LMTD =
var _max1 = if(isfiltered('Date'),MAX( 'Date'[Date]) , today())
var _max = date(Year(_max1), month(_max1)-1, day(_max))
var _min = eomonth(_max1,-2)+1
return
CALCULATE([net] ,DATESBETWEEN('Date'[Date],_min,_max))

Last Month =
var _max1 = if(isfiltered('Date'),MAX( 'Date'[Date]) , today())
var _max = eomonth(_max1,-1)
var _min = eomonth(_max1,-2)+1
return
CALCULATE([net] ,DATESBETWEEN('Date'[Date],_min,_max))

Power BI — Month on Month with or Without Time Intelligence
https://medium.com/@amitchandak.1978/power-bi-mtd-questions-time-intelligence-3-5-64b0b4a4090e
https://www.youtube.com/watch?v=6LUBbvcxtKA

Time Intelligence, DATESMTD, DATESQTD, DATESYTD, Week On Week, Week Till Date, Custom Period on Period,
Custom Period till date: https://youtu.be/aU2aKbnHuWs&t=145s