Checkbox and countif

Hi everyone,

I'm experiencing an issue with checkboxes in Excel Online. I have a table where I use checkboxes (TRUE/FALSE) in five rows, and below them, I use the following formula to count how many checkboxes are checked:

=COUNTIF(F1:F5,TRUE)

However, when I check a box, the counter briefly updates (e.g., from 0 to 1 if only one box is checked) but then immediately resets back to 0 within a second, as if the checkbox is being unchecked in the background.

This behavior does not occur in the offline (desktop) version of Excel, where everything works as expected. Additionally, after reloading the page, sometimes the checkboxes reset to an unchecked state, and other times the counter updates correctly.

Is there a known issue with checkboxes in Excel Online, or is there a setting I might have misconfigured? Any advice would be greatly appreciated!

Thanks in advance.