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Are both Parent Monitor's saying "Not Linked" on them even if their 3 feet away from the baby unit? Try removing the power completely from just the Baby Monitor for 60 seconds then plug it back in with the Parent Monitors being about 3-4 feet away. Give it about 1 minute to allow for them to sync up to each other. After 1 minute, press the Find/Page button on the Baby Monitor and see if the Parent Monitor's are paged. If not, then the Baby Monitor's Transmitter has gone out in it. Reset the Parent Monitor's back to Factory Defaults and try again just to be sure. If the Monitor is still under warranty and still isn't Linking, you'll need to get an RMA from Vtech and they'll send you a working one. Hope this helps my friend and please remember to indicate that I have helped you today.