Chart in Calc does not update after being saved

My issue: One of my colleagues is working on a chart in libre Calc. Basically, data on the X side should be in 90° position, but they’re always in 45°. The chart is in Calc and is required to be in .xlsx format, as it will be later used in Microsoft office by another colleague. However, when I change the X to 90°, click off the chart to save it in xlsx(as having the chart selected will only give me the option to save it as .odc), close the file and open it again the X returns to 45°.

I’ve tried to look up for multiple suggestions but so far I have not found a solution.
Forcing Shift + Ctrl + F9 or automatic saving on/off does not help.

FYI, the data in the file is connected to other files. I don’t think it’s the reason why it moves back to 45° but just putting it here in case if it’s related.

Are you able to save in xls format instead of xlsx? This seems to work around the axis label rotation issue, but not sure if it works ok for connections to other files.

In general LibreOffice compatibility with Excel is better in xls files than with xlsx.

Yes,thank you. That fixed the issue I was having.