Welcome to the Virgin Community! I'm so sorry to learn about the problems you're experiencing with your phone line at the moment.
I've been able to locate your account to take a closer look at this from our end for you. I can see you've been able to test this yourself and arrange for an engineer to come and take a closer look, I'd love to hear how that goes!
I'm sorry again for the inconvenience this is causing, we're looking forward to putting it right.