Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
What maker and model of phone is it?
And what type of phone line service do you have, please? (e.g. digital, UVerse, MagicJack, Comcast, landline, etc.)
OK. Thanks for responding.
Do you have any other phone to try on the line?
Or, any other phone, e.g. to contact Telstra with, in case the 'Check Tel Line' message actually means the telephone line has a problem?
Or try the Troubleshoot Now blue icon on the right, on this page:
Let me know if that produces a useful result, please.