Totals not matching

I have issues with the total readouts of my flukso meters.

When I do the following:
- read the meters visually each month at a given time (both gas and elek)
- export the data between those two times with with 15min interval

The totals aren't correct. My elektricity use is ~45% to 50% of the visually read use, the gas use is ~90% of the visually read use.

Did anyone else experienced this issue, are there possible tips of things to do to solve this issue?