Have you checked to see if there is aproblem in your area using the status page.
https://www.bt.com/consumerFaultTracking/public/faults/tracking.do?pageId=31
If there is not a general problem you need to contact BT and report a telephone fault and they will check the line for you.
You have no internet because you have no dial tone. Report a landline fault. Don't mention broadband.
See link
You can use chat to report no dial tone.