Based on your description, this problem occurs in PowerPoint for Windows and PowerPoint for Web with specific fonts.
Is my understanding correct?
What version of PowerPoint did you use?
I tested in my PowerPoint 365 version number: 2301, I cannot reproduce this problem:
I suggest you install the last updates for Office and check the result.
You can also try to repair Office application: https://support.microsoft.com/en-us/office/repair-an-office-application-7821d4b6-7c1d-4205-aa0e-a6b40c5bb88b
Please provide more information about this problem so that I can get more accurate solutions to this problem. I’m glad to help and follow up your reply.
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