They just didn’t try hard enough. I tried calling my energy provider. You have to call more than 5 times, to even get to the robot call system. Other times they line is just dead. Then you have to listen to adverts over adverts and at the end the line just goes dead again. Trying the same number with with landline or mobile also gives differrent results, I once or twice got to the point where I it might have ringed some phone. but after a couple of rings, the line just goes dead again.