Passing a Variable not working

Hi everyone,

I hope you will be able to help me to understand why the variables in DAX do not work as expected.

If I create a measure as the below, it doesn't work (doesn't return the desired outcome):

x_Achieved = 
VAR CurrentQTR = LOOKUPVALUE(Dates[Academic_Year_Quarter],Dates[Date],MAX(c_Enrolments[Date Exported On]))
VAR IsAchieved = FILTER(c_Enrolments,c_Enrolments[CompletionID]=2 && c_Enrolments[OutcomeID]=1 )
RETURN CALCULATE(COUNTROWS(c_Enrolments),FILTER(Dates_AED,Dates_AED[Academic_Year_Quarter]=CurrentQTR),IsAchieved)

Once I change the CurrentQTR to an actual string, it seems to work correctly (returns what is expected):

x_Achieved = 
//VAR CurrentQTR = LOOKUPVALUE(Dates[Academic_Year_Quarter],Dates[Date],MAX(c_Enrolments[Date Exported On]))
VAR IsAchieved = FILTER(c_Enrolments,c_Enrolments[CompletionID]=2 && c_Enrolments[OutcomeID]=1 )
RETURN CALCULATE(COUNTROWS(c_Enrolments),FILTER(Dates_AED,Dates_AED[Academic_Year_Quarter]="22/23 - Q4"),IsAchieved)

When I evaluate the CurrentQTR calculated using the LOOKUPVALUE and pass it into a Card visual, it shows exactly the desired value, "22/23 - Q4".

I am baffled as I have no idea why it has decided not to work...

I am sure it must be something silly and simple, but I am stuck.

Many thanks for your time 🙂