Welcome to the forums, @Catnip . You obviously have a major problem there, so:-
First thing to check: Is your phoneline clear? Dial 17070 (preferably from a corded phone), select option 2. Once your phone number is confirmed, there should be silence on the line except for the regular 'Quiet Line Test' message - any other noise, report a PHONE problem via: https://www.plus.net/help/report-a-problem/phone/
If the phone test passes, report a broadband problem via: https://www.plus.net/help/report-a-problem/broadband/
Let us know the result - if the tests come back as clear but you still have a problem, we need to investigate further.
The above assumes you still have 'normal' landline connection - if you have a SOGEA (internet only) one, just use the second link to report a network issue.
John
