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I have an LG Voyager phone and the select family share plan. There is a person who aquired my number and keeps calling me and I would like to block his number, however, the only way I can see to do that is to sign up for a plan that costs $4.99 a month for usage controls. I would like to block this number, but not at the cost of $4.99 a month. Is it possible to block this number without having to pay for a service? If not, is it possible to get my own number changed?