@Yasas Kasthuriarachchi - could you move this to https://community.ifs.com/groups/alliance-265?
This is really odd.
So it seems if you create a report from scratch it will allow the data but if I make a change at a later date, then it reports less data? not a later time?
Take a quick look in the “Retrieve Limit” module...see if there are any entries in there that are set to a value of 8600 records (and if so increase the number and see if that resolves the issue).
Report limitations are stored in the global.xml and managed by the configuration editor. I believe the default limit is 10000 rows. Can you review if whether adapting the Report Record Limit setting in the Configuration Editor - Globals section will allow you to retrieve the 35000 rows.
As a side note, exporting a large number of records has a potentially serious impact due to large datasets and I presume you are running the report from your client thus even more sensitive. I would not advise making this value too large.