Thank you for your answer ZHU,
However, we have a different problem. We checked and this error only occurs with one Vendor, when we have other Vendors with simillar dataset and no problem.

But we can run the same report from report layout selection page, no problem

The same report for order 106019 we cannot generate from purchase order page. The problem is that system does no even show the filter page to preview a report.

As you see we can open a report for another order with another Vendor. And even if I change the filter to the no. 106019, the report is generated without problems.
I tried to create new order with the problematic Vendor and the same error occurs. As we can easily run the report from the report layout page, the problem seems very wierd.
Thanks in advance