This is my first time using modern charts in Access. I built a query that counts the amount of parts returned by each customer for a date range, and gives me the top 10 results, descending by return count. Exactly how I want it.

I go to use this query to make a chart, and what I end up with is every single customer displayed on the X axis, with all their counts on the Y axis. Based on the query that was nicely ordered and limited.

So I'm looking at the Transformed Row Source, seeing that there's basically a new query superseding my original query. So then I tried using a simple query that just pulls in the relevant information from the two related source tables, and then building a chart off that so I can just edit the Transformed Row Source and... no matter what I do, it tells me

"You can't assign a value to this object
* The object may be a control on a read-only form
* The object may be on a form that is open in Design view
* The value may be too large for this field"

The first reason doesn't make sense, as I'm actively editing the report, and its not a form.
The second reason still seems to not apply, since this is a report, and the only way to access that property anyway is to view the report in design view.
The third reason is right out the window

Any idea how I can wrangle this program to work with me here?