I have been called not once but twice today by a recorded message claiming falsely to be from "BT internet department" and threatening to cut off my landline and internet service.
If you get such a call, HANG UP, do not press any buttons on your key-pad, ignore the message and do not return the call.
This message is not from BT.
BT would never contact customers in this way.
This message is from fraudsters and crooks who are looking for a way to rob you.