453. failed to upload file

[user_726524837326986_726524837326986]

I'm using RLC-511W. I connect the network through HSAirPo outdoor modem and using a ESP 32 as ftp server. I'm inputting correct IP, port, username, and password, and ESP32 receive the callback when i do "test" in ftp server. But somehow it's stop sending and give prompt error like this:
"453. failed to upload file. please check: if your ftp server is full. if you have permission to upload file.". When i check in the sd card, i found the file "test.txt" but there's nothing inside the file.

[joseph_1979]

@user_726524837326986_726524837326986 Grant full permission on the ftp server. Try to install cerberus ftp server on your pc and check if this is triggered. A wireshark trace in both scenarios can help you identify the issue.