Handle connect callbacks are not working in Tapjoy unity android

Question

I have used Tapjoy to show offer wall in my game. It works fine in the sample app given by the Tapjoy plugin for unity. I have provided my Android SDK key. But it does not work in my game. I found that Tapjoy.IsConnected shows true, but either HandleConnectSuccess or HandleConnectFailure callbacks were not called. I have even checked the internet connectivity. Please help.