It's necessary to setup up a PayPal Business account correctly in order to make it work properly with TuoTempo.
2. Login using the Admin Paypal Account
3. select "More options"
4. choose the following setting on the option : Do you want to use the same encoding for data sent from PayPal to you (e.g., IPN, downloadable logs, emails)? > No > Utf-8
5. Save the new settings