Thank you for letting us know. I understood it was on Test out because I saw that you were moving through the course quickly. Let me explain. The team of contributors writes the course - all the sentences etc. And we administer the course as now we are communicating. However, certain areas are done on the Duobot which is the computer program and that's where this problem comes up.
When we edit or fix a sentence it sometimes doesn't go to the Duobot, so the Duobot only accepts the very first sentence we ever wrote. That happens on Test out, multiple choice, Strengthen Skill (a lot), listening and some other areas. So, I'm sorry about the "sum, total" problem.
We keep reporting it to Duo but it doesn't seem to be fixed yet. Please be patient and best of luck on Duo.
Thank you, for the follow and don't hesitate to ask any questions you have and to give input which helps us a lot.