Queued uploads not working

When I try to upload a file via the queue, it tried to establish a new connection and then I got the error 530 that only one Login is possible.
When I do it without the queue it works fine.
"Reuse connection" is enabled.

[23:12:59] Resolving host name "ftp.stadt.heim.at"
[23:12:59] Connecting to Port: 21
[23:12:59] Connected to ftp.stadt.heim.at.
[23:13:09] 220 STADT.HEIM.AT FTP-Server ready.
[23:13:09] USER 131204
[23:13:09] 530 Nur ein gleichzeitiges Login ist moeglich.
[23:13:09] Active Help: https://www.smartftp.com/support/kb/51