This might be the limitation of Matrix Visual that you cannot scroll horizontally along the Row Headers. A work around for this can be to increase the width of the canvas so you can scroll the canvas along the horizontal axis and this would allow you to use more fields in matrix row hierarchy. For that unselect the visual and go to the "Format Page Settings" by following the steps in the attached SS
After that go to the Zoom setting at the bottom right of corner and adjust the zoom where it fits the height and allows you to scroll along the horizontal axis.
Thanks Vanessa for your response!
Attached screenshot.
As you can see in the screenshot, Values are not seen.I am aware that i can reduce the width of rowheader to see the values but i am yet to add 10more fields to the rows .Reducing width of rows might help for few fields but when more fields are added this clearly wouldnt help me 😞 
Hi @JP1983 ,
This is a known limitation for the current release of the Matrix visual which you could see the tip on the upper left corner of the visual.
As this post said, the matrix doesn't support so many columns. It seems to support up to 100 columns. It won't show all these column values. As a workaround, you could consider insert a slicer to dynamically filter matrix columns.
https://community.powerbi.com/t5/Desktop/Too-many-values-Not-showing-all-data-in-Matrix/td-p/412759
Best Regards,
Yingjie Li
If this post helps then please consider Accept it as the solution to help the other members find it more quickly.
You have an issue with the model and how you are adding data. But this is very difficult to troubleshoot without access to a PBIX file to play with.
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Thanks @edhans & @v-yingjl for your quick response.
Perhaps i haven't explained clearly.
I have made the font color as "White" due to confidential data.I have no issue with returning data neither report and it works fine.
The issue is with the display of Matrix.
What i meant was when more fields are added to "Rows" (highlighted in screenshot ) section, the measures i.e on "Values" section are not be seen.Inorder to view the measures i will need to reduce the "row" width.
In the attched screenshot you cant see the measures and the scroll bar doesnt scroll the page but only the measures.This i noticed when i removed few fields off the "Rows"section.
Sorry, I still don't get it. You are in a table view of the visual (that is why it says "Back to report in upper left), not the actual visual itself, so I still don't know what the issue is with the Matrix visual itself.
I have attached the pbix sample here Pbix Sample Report Link
In the attached report, you can see fields until "Date" and the rest (Promotion,ID and measures)are not shown in the matrix though they are exist in the visual.
Is there any way showing all of them without reducing the font size or number of fields ?
You've just put too many columns in the rows. It is more than a screen can show. I shrank the font really small and i can just begin to see the values columns below.
When I change it to a stepped layout, you can clearly see what is going on. There are your value columns and you 12+ row columns in a stepped format. You just cannot show everything in a non-stepped format with that many rows. It is like filling up your Excel screen with a lot of columns and freezing the columns at column R or similar. You'll never see what is in column S because A-R fill up the screen.
@edhans Thanks for your explanation.
I am aware if i reduce the font size, i will be able to see all fields but I am trying to understand the limitation here :
1. is it not possible to show all fields in rows in non-stepped layout without reducing font size ?
2. Is it possible to unfreeze the "rows" column ?
- No. What if you had 100 fields? 1,000? Would you expect to see them all? You just have right around the number of fields in your rows that is causing this issue to manifest itself.
- No. Rows are always locked/frozen. That is how a matrix works. If you want to do side scrolling, you'd need to make it a table, which has its own limitiations, which is why I'm sure you picked a Matrix in the first place.
