Numbers have issues for some reason. Even if you literally play the Duolingo's original audio back to it during the speaking exercise, it will not register it. It's something on the deeper level of Duolingo that volunteering contributors/moderators have no influence on; I've notified the Duolingo staff already. It's not only for this exercise, it's a general thing. One person from the Norwegian course commented that they have similar issues.
I've heard this problem being mentioned several times. As a Duo contributor, I have no access to this part of Duolingo. I don't know how the recording works, and how it later matches the recording to the original sentence and decides whether it's right or wrong, what kind of programming languages they use for this and so on. This is something the Duolingo staff does, not the contributors.
I will try to contact the staff and ask what the bug/glitch could be caused by.
Please remain civil in the comments. Duolingo is a website/software just like any other, it might have bugs or unforseen strange behaviour. Bugs are quite a normal part of life and we have to deal with them at some point.
As a side note, I find it a bit unhealthy that an app makes you so incredibly angry. You might want to analyse your emotional reactions and see if you think they are OK.