Don't make your Android app free for 1 day
I had this exact problem.  This is one of the reason I have found the Android app market horrible when compare with the iPhone market.  This rule is so arbitrary and non-intuitive.I actually made my app free for testing purposes and had to create an entirely different app once I made it free.In my experience with the Android app store, Google has no idea what they are doing.Edit:
Independent of this weird issue, I say this mostly because we sold literally 20x less of the exact same app on the Android market vs. the iPhone market (the apps were marketed the exact same way).  This is in spite of the fact that the Android phone sales are apparently equal the number of iPhones phone sales...Another one of my biggest gripes, while people are listening, is that you can not get a URL for your app for the Android store (or at least I don't know how).  How are you suppose to sell anything on the web without a web address.  We have a link to our iPhone app and for then Android app we need to give people a search term to enter into the Android app store!  This is crazy to me!Finally, and this is the last thing I promise, when you submit and app to the Android store you use a keystone to sign it.  Well, I ended up losing my keystone (cause I'm an idiot), so I could never push an update of my app.  So, I ended up needing to go through and literally refund 100 people's purchases (by hand) and create an entirely different app. This was actually the same app that I made free, so I literally have 3 versions of this app submitted to the Android App Store (but two are no longer public).