Correct a long term statistic

When I try to correct a statistics of some sensor under developer → statistics but the icon on the right side to correct the statistic is not showing up. The icon I am looking for normally looks like a ramp.
It only states “no problem” and the place where this icon should be is blank.

How can I correct values of sensors which have “no problem”.

You can only correct sensors that have the state class total or total_increasing.