LFTP: mkdir -p -> Error: File exists?

Question

FTP

What kind of misfortune is this with lftp?
I'm trying to create a directory:

lftp -c "set ftp:list-options -a;
open 'ftp.some.com';
mkdir -p /some/folder/new/;
";

If the directory does not exist, it is created. When restarted, it gets hung up on mkdir.
Error in logs

---> MKD /some/folder/new/
<--- 451 Error: File exists.

The latest version. Already tried all "set ftp:*" options...

Answer 1

Try using the -f switch like this:
mkdir -p -f /some/folder/new/;

Answer 2

So far I decided with a separate call

lftp -c "set net:max-retries 2;
open 'ftp.some.com';
mkdir -p /some/folder/new/;
";

But it's kind of dumb.