Thank you for the responses. Since they come in a two pack, I'll try setting up the other one. It's likely to be a fluke, it happens. It won't stop me from getting more. It was great while it lasted. It also may be my fault. When I downloaded the app, it wanted to update but the update failed, hopelessly locking up my phone. Googling has shown that it may be a problem with the Android phones. I uninstalled the app completely and downloaded it again. This time it did not ask to update. When I first installed the plug, it did work, turning on in the morning and off at night. We call our area the "Newaukum triangle", (where I live near Enumclaw) as electronics and tractors frequently fail, lol. Anyway, thank you for the input. I love aquariumcoop and all the products, Wendy