You should include your own configuration file. username must have your cell phone number without any country code or plus sign. password must be the one you use on cubacel dashboard

config.json or micubacel_config.json

{
    "login": {
        "language": "en_US",
        "username": "123456789",
        "password": "qwerty",
        "uword": "-",
        "": "on"
    },
    "data_path": "~/.internethistory.json",
    "cookies_path": "~/.cookie.json"
}

By default the files config.json or micubacel_config.json are search in the current working directory, if are't fount the the files .config.json or .micubacel_config.json are search in the home folder.

[Unit]
Description=Pycubacel parser
After=network.target

[Service]
User=youruser
ExecStart=python -m pycubacel server /path/to/config.json
Restart=always

[Install]
WantedBy=multi-user.target