Hi, months later, I found the solution in another forum. We have to change the “ip filtering” enketo configuration, the file is in ~/kobo-env/enketo_express/config.json.
Notice that when the server is in a private datacenter, usually the public IP is not directly associated with the machine, so thats why we have to change the allowPrivateIPAddress property to true.
"ip filtering": {
"allowIPAddressList": [],
"allowMetaIPAddress": false,
"allowPrivateIPAddress": true,
"denyAddressList": []
},