Good day, WarrenOrlandi-Phillips - WPO.
Welcome to the Microsoft Community Forum. Please accept our warmest greetings and our sincerest hope that all is well.
The PIVOTBY function is currently rolling out to users enrolled in the beta channel for Excel. Refer to link below.
With that in mind, can you tell me what version of Excel are you using? I specifically need the product name and Version number as highlighted in the guide and photo below.
Also, you are referring to PIVOTBY as described in the guide below, right?
https://support.microsoft.com/en-us/office/pivotby-function-de86516a-90ad-4ced-8522-3a25fac389cf
If you already have the required build of Microsoft 365 Insider (beta channel) and still do not have the PIVOTBY function, you may want to post a question over at our Microsoft Q&A website using the link below. They may have the experts that can help you.
https://learn.microsoft.com/en-us/answers/tags/9/m365
If you have additional questions or concerns, please let me know so we can explore other solutions.
Hope to hear from you soon.
Sincerely,
Glenn Rue
Forum Moderator
Microsoft Community