I removed the extraneous code used to set focus and I changed the If structure so that the main logic is not buried in a nested if. I did that by exiting the sub when an error is found rather than continuing.
I formatted the rest of the code so you could see how the indenting should be done. Whenever you have an If or a loop, the code should be indented until the end of the nested part and then the else or the next is aligned with the If or loop.
Then I realized that the loop was wrong and was not ending when it should so I commented out all the code relating to the loop.
Then I noticed that the report name you opened was different from the one you were writing to the PDF.
You can uncomment the code and fix the loop but if you fix the loop, the process will not take anywhere near as long as it was. I think you were looping 6000 times as you incremented the loop counter from 4000 until it exceeded 100000. Put a stop in the code and watch while it executes. That will help you to see the logic error.
It seems to be working but the report is nested too deeply and is not set up like I suggested. The subreport should be the main report. You might want to think about the report structure again because that is probably what is causing the summary to not appear when it should. Also, the headers are not repeating as they should and that might get fixed if you fix the report structure.
The Main report should be bound to the airlines. The subreport should be the transaction detail. The summary should go in the footer of the airline section of the main report.
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