This is what i put together for ftp using an sim7000A, it hopefully will be a similar process to your sim7080G.
If you aren’t using ftp you only need to go as far as AT+SAPBR=1,1 which opens a TCPIP tunnel for data communications.
AT+CPIN? //Check for sim card ready status
AT+CGDCONT=1,“IP”,"" //configure ip address connection type
AT+CSQ //Check signal strength
AT+CGATT? //Check attachment
AT+CGNAPN //Checks if the cell tower provided APN settings for the provider (sim card owner ie hologram.io)
AT+COPS? //Check what operator we are connected to (confirms connection to provider/sim card owner ie hologram.io)
AT+CNACT=1 //Opens PDP connection (provides ip address)
AT+CNACT? //Confirms PDP connection by revealing current ip address
AT+SAPBR=1,1 //Opens a IP tunnel inside the sim7000, allows FTP use
AT+SAPBR=2,1 //Confirms open tunnel by showing current ip address
AT+FTPCID=1 //Sets FTP configuration to bearer 1.
AT+FTPSERV=“FTPSERVER” //ftp server
AT+FTPUN=“username” //FTP username
AT+FTPPW=“password” //FTP password
AT+FTPPUTNAME=“test.txt” //name of file
AT+FTPPUTPATH="/" //path of file
AT+FTPPUT=1 //Attempts to connect to the FTP server, Must wait for response, example: +FTPPUT: 1,1,1360 The last number is how many bytes you can send in one upload.
AT+FTPPUT=2,10 //Send 10 bytes of data
1234567890 //The data. no return, will automatically stop after 10 bytes are received
AT+FTPPUT=2,0 //Close connection to FTP server
AT+SAPBR=0,1 // Close bearer