Sometimes in Jam group, the content preview of files are different with the actual file.
For example, the font style and text color in the file will be different.
SAP Jam Collaboration
The reason causing the issue is that when we view the excel file on Jam, the file is open by the browser, not by the office software, so sometimes there will have difference in displaying.
Please download the file and check the content instead of checking file in preview mode.
2082886 - How to enable Content Administration Mode - SAP Jam