Hi,
You have not pasted enough information for me to know the error. You can paste the entire stack trace (as text, no need for a screen shot), or even better, if you have access to the server logs (django logs), you can see the entire stack trace there. You can also paste the relevant code if you need more help.
For now, I can only recommend you to watch at line 68 of file .../web_server_moip.py, your error is being detected there. You are using a 'decode' attribute of some variable, but that variable contains a str object (string text), and do not have such 'decode' property. The problem is probably because you are expecting another type of object like bytes or bytearray.