Default Home Key comes up Clock app

Hello,
Today, I noticed that my home key is not working the way it was working before. I think that in being in my pocket changed some settings. Basically, the home key (the big button in middle bottom) does not show the home screen, but it opens up the Clock app. I am looking online and on my phone, but I can't find the setting. Please help.

Thanks

Edit: nevermind, found it. It was the Solo launcher settings. How do I delete this thread?