Model: Personal Series LCD Clock
This may be due to may be due to batteries were inserted without allowing power to drain from the clock.
Remove the batteries, wait 10 seconds, and then re-insert the batteries
During initialization (power on or reset) of the clock, its receiver searches until signal from a Transmitter is found, scanning rapidly through 72MHz channels. The receiver looks for a signal for 1 minute, and then switches to scanning in 30 minute intervals until its receives a signal from a Transmitter. Normal operation begins once a signal is received.