When I go inside RBD-3060 task (the first one), I see that this task was created by Lukas, Dawid is assigned to that task and only Dawid have logged hours for this task.
There is also NO Andrzej in the whole history of this task.
How can I prepare trustworthy reports per Assignee if Assignee dimension returns bad values?
This is caused by the “Hours spent” measure finding some relations in this issue to Andrzej. Did you also check the “Activity” and “Comments” tabs for any inputs from Andrzej?
In this case, when using the “Hours spent” measure, you can apply a “> 0” filter to the “Hours spent” Column to filter out these empty references. These references are a by-product of using several dimensions in the Rows sections together with a measure that also checks the historical values of issues.
Please note that when the “Hours spent” measure is used together with the Assignee dimension it will return the total number of hours spent for the issue that the Assignee has, even if those hours were logged by a different user. For this, please, check out the “Logged by” dimension.