FXP between 2 Ubuntu Boxes from Windows

[HFU666]

I have two Ubuntu boxes with the IP addresses 192.168.2.50 and 192.168.2.53. I have on Windows Flash FXP. The normal ftp between Ubuntu and Windows is working. I am using tnftp on Ubuntu.
Now I want to use FXP between the two Ubuntu boxes (transfer directly between the two Ubuntu boxes). I just get the error in Flash FXP:

FlashFXP 5.4.0 (build 3970)
Support Forums https://www.flashfxp.com/forum/

Winsock 2.2 -- OpenSSL 1.1.0e 16 Feb 2017
[L] Connecting to 192.168.2.50 -> IP=192.168.2.50 PORT=21
[L] Connected to 192.168.2.50
[L] 220 bftpd 2.1 at 192.168.2.50 ready.
[L] USER root
[L] 331 Password please.
[L] PASS (hidden)
[L] 230 User logged in.
[L] SYST
[L] 215 UNIX Type: L8
[L] FEAT
[L] 211-Extensions supported:
[L] XPWD
[L] EPRT
[L] EPSV
[L] ALLO
[L] APPE
[L] MDTM
[L] XCWD
[L] XCUP
[L] XMKD
[L] XRMD
[L] REST
[L] SIZE
[L] 211 End
[L] PWD
[L] 257 "/" is the current working directory.
[L] PASV
[L] 227 Entering Passive Mode (192,168,2,50,189,60)
[L] Opening data connection IP: 192.168.2.50 PORT: 48444
[L] LIST -al
[L] 150 BINARY data connection established.
[L] 226 Directory list has been submitted.
[L] List Complete: 2 KB in 0,09 seconds (2,1 KB/s)
[L] Calculating timezone offset of server...
[L] MDTM "µ¢0*µ¢
[L] 213 20170902032500
[L] Timezone offsets: Server: 7200 seconds. Local: 7200 seconds. Difference: 0 seconds.
[R] Connecting to 192.168.2.53 -> IP=192.168.2.53 PORT=21
[R] Connected to 192.168.2.53
[R] 220 bftpd 2.1 at 192.168.2.53 ready.
[R] USER root
[R] 331 Password please.
[R] PASS (hidden)
[R] 230 User logged in.
[R] SYST
[R] 215 UNIX Type: L8
[R] FEAT
[R] 211-Extensions supported:
[R] XPWD
[R] EPRT
[R] EPSV
[R] ALLO
[R] APPE
[R] MDTM
[R] XCWD
[R] XCUP
[R] XMKD
[R] XRMD
[R] REST
[R] SIZE
[R] 211 End
[R] PWD
[R] 257 "/" is the current working directory.
[R] PASV
[R] 227 Entering Passive Mode (192,168,2,53,196,239)
[R] Opening data connection IP: 192.168.2.53 PORT: 50415
[R] LIST -al
[R] 150 BINARY data connection established.
[R] 226 Directory list has been submitted.
[R] List Complete: 871 bytes in 0,09 seconds (0,9 KB/s)
[L] CWD tmp
[L] 250 OK
[L] PWD
[L] 257 "/tmp" is the current working directory.
[L] PASV
[L] 227 Entering Passive Mode (192,168,2,50,211,18)
[L] Opening data connection IP: 192.168.2.50 PORT: 54034
[L] LIST -al
[L] 150 BINARY data connection established.
[L] 226 Directory list has been submitted.
[L] List Complete: 818 bytes in 0,11 seconds (0,8 KB/s)
[R] CWD tmp
[R] 250 OK
[R] PWD
[R] 257 "/tmp" is the current working directory.
[R] PASV
[R] 227 Entering Passive Mode (192,168,2,53,189,82)
[R] Opening data connection IP: 192.168.2.53 PORT: 48466
[R] LIST -al
[R] 150 BINARY data connection established.
[R] 226 Directory list has been submitted.
[R] List Complete: 837 bytes in 0,11 seconds (0,8 KB/s)
[R] Calculating timezone offset of server...
[R] MDTM automounter.suspend
[R] 213 20171008135820
[R] Timezone offsets: Server: 7200 seconds. Local: 7200 seconds. Difference: 0 seconds.
[L] TYPE I
[L] 200 Transfer type changed to BINARY
[L] SIZE sayno
[L] 213 23
[L] MDTM sayno
[L] 213 20171008134716
[R] TYPE I
[R] 200 Transfer type changed to BINARY
[R] SIZE sayno
[R] 213 20
[R] MDTM sayno
[R] 213 20171008114444
[L] PASV
[L] 227 Entering Passive Mode (192,168,2,50,210,7)
[R] PORT 192,168,2,50,210,7
[R] 500 The given address is not yours.
Site-to-site Transfer Failed! (Attempting alternative method)
[R] PASV
[R] 227 Entering Passive Mode (192,168,2,53,230,112)
[L] PORT 192,168,2,53,230,112
[L] 500 The given address is not yours.
Site-to-site Transfer Failed!
[R] Transfer Failed: /tmp/sayno
[L] PASV
[L] 227 Entering Passive Mode (192,168,2,50,170,224)
[L] Opening data connection IP: 192.168.2.50 PORT: 43744
[L] LIST -al
[L] 150 BINARY data connection established.
[L] 226 Directory list has been submitted.
[L] List Complete: 818 bytes in 0,05 seconds (0,8 KB/s)
[R] PASV
[R] 227 Entering Passive Mode (192,168,2,53,187,62)
[R] Opening data connection IP: 192.168.2.53 PORT: 47934
[R] LIST -al
[R] 150 BINARY data connection established.
[R] 226 Directory list has been submitted.
[R] List Complete: 837 bytes in 0,06 seconds (0,8 KB/s)
Transfer queue completed
Transferred 0 Files (0 bytes) in 0,14 seconds (0,0 KB/s)
1 File Failed

Do I need something special on Ubuntu or Windows to make it work?