Numbers appear as time in Calc

I have a column formatted as numbers (#.0) which should appear as 9.2 for example. However, when I type 9.2 what appear in the cell is 04:48. It shows as 9.2 in the formula bar and also as 9.2 in the formatting preview window.
By experimenting I discovered that any whole number appears as 00:00 and any decimal number will show as some kind of time.
I have many other spreadsheets formatted this way that work properly. Brand new spreadsheets also work as expected.
I have spent hours for some hidden setting that may have been accidentally changed, but haven’t found anything. Does anyone have any ideas what could be wrong?

.xls ?

This is the guide - How to use the Ask site? - #3 by Hrbrgr

Please upload a sample file here.

9.2 is the internal floating-point-value for Date-Time »1900-01-08 04:48« … nobody except you may know why there’s the time-Format HH:MM applied!

1 Like

I think if you upload a fragment of the problematic file, the collective mind will find a solution in a short time.
Note @karolus’s answer and that the HH:MM format can be set, among other things, through conditional formatting.