Sorry that you haven't been able to get through. Our phone lines arn't the best way to get through to us at the moment due to COVID-19
I would suggest trying to troubleshoot the issue as this sounds like it might be the modem, This Article shows the troubleshooting steps to follow
If you still can't connect after following the above artcile, I'd really recommend getting in touch with our team on Messenger so we can take a look.
Please note, our Messaging team are currently experiencing delays so it's best to complete some basic troubleshooting before getting in touch with them:
Check wall sockets, power cables and your modem equipment is plugged in, clear from obstructions, and are not damaged
Try alternate cabling if available, and/or replace damaged cabling.