Adding Power BI date range fix to troubleshooting guide (microsoft#1010)

Co-authored-by: Arthur Clares <[email protected]>
Co-authored-by: Michael Flanakin <[email protected]>

docs/_resources/errors.md

@@ -348,6 +348,20 @@ If you see these values, please re-export the cost data for that month. If you n
 
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+## Power BI: Reports are missing data for specific dates
+
+If your report is missing all data for one or more months, check the **Number of Months**, **RangeStart**, and **RangeEnd** parameters to ensure the data is not being filtered out. 
+
+To check parameters, select **Transform data** > **Edit parameters** in the ribbon or select the individual parameters in the **🛠️ Setup** folder from the query editor window. 
+
+- If you want to always show a specific number of recent months, set **Number of Months** to the number of closed (completed) months. The current month will be an extra month in addition to the closed number of months.
+- If you want a fixed date range that does not change over time (e.g., fiscal year reporting), set **RangeStart** and **RangeEnd**.
+- If you want to report on all data available, confirm that all 3 date parameters are empty.
+
+See [Set up your first report](../_reporting/power-bi/setup.md) for additional details.
+
+<br>
+
 ## Power BI: Reports are empty (no data)
 
 If you don't see any data in your Power BI or other reports or tools, try the following based on your data source:

docs/_resources/troubleshooting.md

@@ -110,6 +110,15 @@ Decide whether you will connect to storage using a user or service principal acc
 ### Step 2: Troubleshoot connection errors
 
 1. If you try to connect to your storage account and receive an error: "Access to the resource is forbidden", it is very likely you are missing a few permissions. Refer back to [Connect Power BI to storage](#step-1-connect-power-bi-to-storage) to ensure you have the correct permissions.
-2. If you ssee an error about access being forbidden, review if the billing account that you are connecting to is correct. Power BI reports are provided with a sample billing account, and if you don't change that to your own ID, you won't be able to connect.
+2. If you see an error about access being forbidden, review if the billing account that you are connecting to is correct. Power BI reports are provided with a sample billing account, and if you don't change that to your own ID, you won't be able to connect.
+
+### Step 3: Troubleshoot missing months of data
+
+1. If the Power BI report does not include entire months of data, confirm the date parameters in the Power BI report by checking **Transform data** > **Edit parameters** in the ribbon. See [Set up your first report](../_reporting/power-bi/setup.md) for details.
+   - **Number of Months** defines how many closed months (before the current month) will be shown in reports. Even if data is exported, data outside this range will not be shown. If defined, this parameter overrides others.
+   - **RangeStart** and **RangeEnd define an explicit date range of data to show in the reports. Anything before or after these dates will not be shown.
+   - If **RangeStart** is empty, all historical data before **RangeEnd** will be included.
+   - If **RangeEnd** is empty, all new data after **RangeStart** will be included.
+   - If all date parameters are empty, all available data will be included.
 
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