Dear L,
Thank you for contacting iTunes Store Support. My name is Roy and I'd be happy to assist you.
I know how disappointing it can be, not being able to enjoy the application "WhatsApp" that you have purchased from the App Store. Don't worry, I will sort this out to your satisfaction.
Lieke, as much as I would like to help you resolve your concern, I could not locate the account being used to purchase the application based on the information you provided. Kindly reply to this email with the right account used upon purchasing the application.
Please also include the order number of the App Store purchase you've made using that account. iTunes Store order numbers begin with the letter "M" or "W," and you'll find them in your iTunes Store email receipts.
You can find your order numbers on your email receipts and in your Purchase History. If you need to review your Purchase History, follow the steps in this article:
http://support.apple.com/kb/HT2727
I look forward to receiving your reply. Once I have the information, I will get back to you. Thank you for being an iTunes Store customer; Apple appreciates your business.
Have a wonderful day!
Sincerely,
Roy
iTunes Store Customer Support