Result Not DIsplay Uisng NextMonth Function

If I understand correctly, you need the count of expiring contracts next month for each record in your table, right?
NEXTMONTH() will get you a column of all dates in the following month.
Maybe something like this would help:

Expiring Contracts Next Month = 
VAR CurrentDate = MAX(Tabelle[End Date])  // To get the date in context
VAR FirstDayNextMonth = EOMONTH(CurrentDate, 0) + 1
VAR LastDayNextMonth = EOMONTH(CurrentDate, 1)
VAR ContractCount = CALCULATE(
    COUNTROWS(Tabelle),
    ALL(Tabelle[EndMonth]),  // Remove the filter context imposed by EndMonth, else the measure would not work, when you add EndMonth.
    Tabelle[End Date] >= FirstDayNextMonth,
    Tabelle[End Date] <= LastDayNextMonth
)
RETURN
IF(ISBLANK(ContractCount), 0, ContractCount)

Hi aschkan 

You are on the right track. It worked like a charm!

Depending on alvin1999 needs, the approach can be modified like this:

Expiring Contracts Next Month = 
VAR CurrentDate = MAX('Table'[Extracted_Contract End Date])  // To get the date in context
VAR FirstDayNextMonth = EOMONTH(CurrentDate, 0) + 1
VAR LastDayNextMonth = EOMONTH(CurrentDate, 1)
VAR ContractCount = CALCULATE(
    COUNTROWS('Table'),
    ALL('Table'),  // Remove the filter context imposed by EndMonth, else the measure would not work, when you add EndMonth.
    'Table'[Extracted_Contract End Date] >= FirstDayNextMonth,
    'Table'[Extracted_Contract End Date] <= LastDayNextMonth
)
RETURN
IF(ISBLANK(ContractCount), 0, ContractCount)

Notes: By the way I am following the steps below to set the Extracted_Contract End Date because after my testing it may cause an error if I use the FORMAT function.

if I use the FORMAT function

Best Regards,
Yulia Xu