Upload file from SD card by Micro SD adapter to ftp server using sim800l

Projects Networking, Protocols, and Devices
1

I use Arduino Mega 2560 to send a file stored in a micro sd by a module "Micro SD adapter" to ftp server. I use the sim800l evb v2.0 module and I proceeded as follows:

I insert the AT command :

AT+SAPBR=3,1,"CONTYPE","GPRS"

AT+SAPBR=3,1,"APN","internet"

AT+SAPBR=1,1

AT+FTPCID=1

AT+FTPTYPE="I"

AT+FTPMODE=0

AT+FTPSERV="197.158.86.105"

AT+FTPPORT=42

AT+FTPUN="user"

AT+FTPPW="password"

AT+FTPPUTNAME="test.txt"

AT+FTPPUTPATH="/"

AT+FTPPUT=1

Results :

+FTPPUT:1,62
sometimes +FTPPUT:1,63
or +FTPPUT:1,64
or +FTPPUT:1,65
or +FTPPUT:1,78

what do I have to do. Please, can anyone help me? thank you