Not Possible to Save

When trying to save a rather big spreadsheet, all of a sudden the following error alert appears:

Errors were detected while saving '/Users/imac/Documents/Excel Sports/Soccer/WTA 2024.xls'. Microsoft Excel may be able to save the file by removing or repairing some features. To make the repairs in a new file, click Continue. To cancel saving the file, click Cancel.

Whatever I try (repairing in various new files) or trying <Safe As> I always get the same error! I also tried to save without Macros.

What can I do in order not to lose the whole spreadsheet?

(Excel for Mac Version 16.32 (19120802) with licence Office 365)

Thank you; the question remains why Excel is not able to tell where the error is and why.