Resolved HTTP/2 stream 1 was not closed cleanly before end of the underlying stream

Hallo,
When exporting products via RO CSVI (VirtueMart) I receive the following messages:

Danger:
HTTP/2 stream 1 was not closed cleanly before end of the underlying stream

Info:
“Are you finding duplicate rows in the export file? Have a look at the Use of Group by and Sort by fields document…”

The export stops after 30 sec

thank you