In my SPO list, I have a flow that is using Microsoft Graph and grabbing teams presence.
The SPO List will have the following columns.
Activity, Availability,TimeStampofState,TimeInState
I am grabbing activity and availability and then marking the TimeStampofState with current date/time.
When it runs again, it checks to see if the status has changed.
if it has, it stamps the TimeStampofState.
If the status has NOT changed, it will take the current time, subtract the TimeStampofState, to give me how long they have been in that state.
This is working....except for half of my SPO List.
I am finding that it is randomly doing this for people in my SPO List.
I am getting the current time
{
"body": "2022-08-23 19:33:17Z"
}
I then take that current time and use ticks and set it to minutes.
DIV(ticks(body('Convert_time_zone_2')),600000000)
This is my StartDate
I then grab the TimeStampofState from SPO and do the same thing:

DIV(ticks(body('Convert_time_zone_3')),600000000)
In the flow the conversion is this for my non working example:
StartDate - 1063281333
EndDate - 1063281329
Now, I SET a variable, to do the difference:
sub(variables('StartDate'),variables('EndDate'))
For some of the people in SPOList, it will subtract the two numbers.
For others, I am seeing this:

It is like it is loading up the variable with only the enddate, thus giving me the negative enddate number. It seems to forget the StartDate. That value is just my enddate with a negative symbol in front of it.
I can't figure out why this is happening.
Again, same list for all, works for some others no.