Since Flash went out of business decades ago, you cannot buy a new manual. However, here are the current best bets:
For each step, ensure the state (ON/OFF) is correctly assigned before saving. Operating Modes flash monotron 124 manual
“The Ghost in the Wire”
Ensure the device is in AUTO mode. If it is in "Manual" or "Prog" mode, it may not follow the set schedule. Since Flash went out of business decades ago,