Welcome to the Community!
Really sorry to hear you're having trouble with your landline.
I've run a diagnostic and I can't see any network issues currently affecting your line. As you've already checked your handset, the next step is to arrange for a technician to check the line.
I've sent you a private message (purple envelope at the top right of your screen) so I can arrange an appointment.
Tech fan? Have you read our Digital life blog yet? Check it out