Thank you template and message not getting

Hi,
I have using the plugin for donation and i like the functionality, unfortunately i didn’t get thank you message as well as Thank you template while i have testing in sandbox account. but i got the new donation notification into the admin. but the complete thank you sections will not getting. i have tested the Send a Test Emailinside the Thank You Template Tab. but not getting mail.
please help me for resolving the same.

Thanks