Data we are sending via WinSCP SFTP will not trigger file imports automatically when the file is rcv

We are running an extract in PeopleSoft that populates a table that we send via WinSCP - SFTP. The automatic trigger when the new/updated file is received works fine with smaller files but does not work at all when larger files are sent/received.
We changed the files to .txt files and changed the Transfer settings to Text with the same result. This change was a global change that will affect any application that uses WinSCP in our organization.

Does anyone have any ideas on the automatic trigger works for small files only?

Any assistance would be greatly appreciated.

Thanks

Maybe the trigger is confused by "transfer to temporary filename" that by defaults happens for files over 100 KB:
https://winscp.net/eng/docs/resume#automatic
Try to turn it off with -resumesupport=off:
https://winscp.net/eng/docs/scriptcommand_put