Hi,
Was the decimal number created by yourself? If not, please try to paste the number in notepad first, then copy paste the numbers to your document.
You mentioned, everything was fine till today. Was there any changes in your OS or office?
Also do you mind to share me a copy (keep just the decimal part which you can’t change font size) to:
ibsofc@microsoft.com? So I can test it from my side. Please use thread link or the subject of this post as mail subject.
Thank you.