Similar scenarios happened to me a few times, including one on financial services comparing 3 institutions all the way to the demographic questions, then kicked me out after I answered the number of adult members in the household!
However on each and every such occasion I used the Contact Us to report it and ask proper credit be manually posted. Each time they posted it the next day with a reply with the last time they even posted less than 3 hours after my request. I have a feeling that these are due to technical issues - because in each occasion in the replies the support reps claimed they were able to locate the survey and knew how much time you spent on it - once they could identify such they would post the credit.

The only time I was kicked out with a reason of This Survey Is Expired - again after the last screen of demographic questions. The rep's response was, it was a technical issue that a survey should not accept participants when it was about to expire. Nonetheless she manually posted the credit.

I understand it is annoying to request survey technical issues, but then I am more annoyed by not getting the rightfully earned credit - as long as they response positively, I would continue with them.

Another thing I notice is, you get a better chance to earn credit on the surveys AFTER the daily 5x 0.20 already given, with the surveys would earned 0 if not qualified - somehow, you get a higher chance of being qualified on those later surveys. May be it is a way for them to test whether the participant is earnest to participate... Just a thought.