File-Zilla upload not working?

I'm currently trying to upload anything to a Minecraft server via FileZilla. Unfortunately, the whole thing doesn't work even with an empty order. Here are the messages in the FileZilla issue after the upload has started:

Command: CWD /

Answer: 250 "/" is the current directory.

Command: MKD

Answer: 501 Syntax error: command needs an argument.

Then the action is simply completed without anything being uploaded. Why is that and how can I fix it?

The question is too poor. Something is missing:

where hosted, access data entered correctly, a server has already been created, which does not work exactly.

Only then can you narrow down your problem.