Issue using Group By within Dataflow.

Hi,

Issue using Group By within Dataflow, how to fix it?

Steps to reproduce

Power BI Service > Workspaces > Dataflows > Create Dataflow > Define new entities > OData > Enter Business Central 261 G/L Entries OData URL.

Remove all columns except:

-G_L_Account_No
-Posting_Date
-Dimension_Set_ID
-Amount

Highlight Posting_Date > Transform > Date > Month > Start of month

Group By > Advanced > Group By all except Amount, SUM Amount

After that it throws the following error:

Expression.Error: The key didn't match any rows in the table.DetailsKey = [G_L_Account_No = "6100", Posting_Date = "2020-04-01", Dimension_Set_ID = 123]
Table = #table({"G_L_Account_No", "Posting_Date", "Dimension_Set_ID", "Amount"}, {})

Tried the same Group By using Document Date > Transform > Date > Month > Start of month which also produces the same error.

Doing a Group By without a Date columns works perfectly well, but I need the Posting Date 😞

Before Group By the Posting Dates shows perfectly well, no errors.

How can this be fixed?? Any suggestions please?