Just to add a bit of humor, I used to have 2 AT&T pots lines at home. Told them to shut one down and as you can image, they shut the wrong one off. After getting it turned back on, I was told that the LD plan I had isn't available and I'd need a new one.
As you can image, my blood pressure was sky rocketed. Told them if they couldn't reinstate, don't want LD. Went for a few years without LD before setting up my Google Voice sip via simonics. Those calls are free now. :-)