Hi Jhon,
We understand that you are encountering an exception issue while
attempting to change the aggregation type for a value field that starts with
numeric text. If this is the situation, please note that it is a known issue
that has been addressed in our Volume 4 Main Release V28.1.33, which
fortunately has been rolled out today. Additionally, we have prepared a sample
with the latest version for your reference. You can find the sample at the
following link.
Sample: https://stackblitz.com/edit/react-nmrzk6-u7dbje2n?file=index.js
Output GIF:

Issue root cause:
The issue occurred because
field names were used as class names for elements, such as buttons, in the
field list. As a result, a script error was thrown in the console when using querySelector() to
fetch the DOM elements. This issue has been resolved by replacing querySelector() with
getElementsByClassName() to retrieve the DOM elements using their
class names.
Furthermore, please refer to the
below release notes for your reference.
Release notes: https://ej2.syncfusion.com/react/documentation/release-notes/28.1.33?type=all#bug-fixes-17
Please let us know if you have any concerns
Regards,
Sridhar Karunakaran.