I too received calls. This raises concerns about how privacy laws are enforced with security companies. They have a duty to protect client information given the nature of their business. The fact that these callers know so much about your account is concerning. Legal action is warranted.
They call, let it ring twice, and then disconnect. They are clearly trying to create a scenario of terror and intimidation. There is possibly a Satanic connection. The calls never are at the same time so I can be away from the phone. The intent is to surprise you and paranoy you.