downloaded the game the walking dead and purchased episode 2 to 5 but cannot open the application anymore and it was already charged to me...what can I do?

Please help me on my problem...I've downloaded and purchased the complete episode of the walking dead game in my ipad 2...after long waiting of the download, there was an error in the end telling that "there was a connection error..." so I assumed that it was not purchased...but after 3 days...a receipt to my email arrived (receipt No.126045604263) that the game was charged...so i tried downloading again the game but unfortunately, I cannot open now even the episode one which is free...upon clicking the icon in my ipad...it will just bring back to home... 😟 please help me with this. thanks.