Hello, the installer told me that there's no need for an antenna if signal value is higher than -10dB. They tested it and indeed, it was higher than that but after installation, I've notice that the signal is really poor. When I check the modem's signal, it went below the value of -10dB. It was just -7dB so I thought requesting an external antenna is a quick fix. Do I have to pay extra? If no, where can I request it? Thank you.