Hey Donna, two ways you can do it. Best and quickest is to go to www.directv.com. Sign into/up for account. Type 721 in the search box. Next page will show a link to 'resend authorizations'. You can also call 1-800-531-5000 but a) you're dealing with holding, and b) I've seen it fail or take a long time to work. Happy Holidays!!
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The DVR Whisperer
I am a DirecTV technician, VERY knowledgeable on equipment from DirecTV
Well 721 means you dont get that channel or that receiver has lost its programming. You will have to call directv in order to fix this, you might get lucky and this might be simple. Try to call 1-800-531-5000, it will be automated. When asks why your are calling just say ( 721 ) and it will reauthorize your receivers. As long as your receiver is on your account (not from a buddy or something) it will come on.