Hi, I have returned to work after parental leave for 18months. I work from home. Before I left we had ADSL and now I'm back we have NBN. Since being back I can't get my phone line to work on my work phone which i use through our computer system. The line seems to die out - the phone makes the sound it does when you forget to hang up the handset. Can you please let me know how to fix this. Thank you.