WinSCP client FTP script download file changes line order and content

WinSCP on Windows Server 2022 Datacenter.
We use WinSCP client to download csv files from FTP server by using script. The transfer option used is BINARY. WinSCP 4.3.5 was working fine for last few years until last week. The file downloaded had the same file size and timestamp but the file content has been changed: some files with the header line moved to the middle of the file, some files cut short. We have tried latest version WinSCP 6.5.6 but it has the same issue. Any help would be much appreciated.

Log files attached.

So do you get the problem consistently? Or is it random? Do you get it with WinSCP GUI too? With other FTP clients? In general, it's more likely a server-side issue.

martin wrote:

So do you get the problem consistently? Or is it random? Do you get it with WinSCP GUI too? With other FTP clients? In general, it's more likely a server-side issue.

Thanks for the reply.
I get the problem randomly - maybe 7 times out 10. Also get it with WinSCP GUI too. Haven't try other clients.