I get the warning "Wait! Some of your past questions have not been well-received, and you're in danger of being blocked from asking any more." I am struggling to find any cause for this; I cannot find any question that has been received badly.

I have a total of 8 questions with an average question score of 2.25; only a single question has score 0 and no question has a negative score. The last question was more than three months ago.

I definitely do not have any recently deleted questions. As far as I can tell I do not have any deleted questions at all.

If I read my reputation history correctly, I have only ever received 2 downvotes, one of which was later undownvoted.

So I really cannot tell what triggered this warning and would appreciate some information here.

Do I have any deleted questions that I am unaware of?

I do have two questions that were closed as duplicates, but even so they have a positive score, so at least they were helpful to someone as a signpost. I also am not sure how I could improve duplicates by editing, and I really would like to take care of this warning before I ask more questions.

None of the related questions here on superuser seem to give any hint that is applicable for my situation. In all these cases there were at least some questions with a negative score involved.

What could have caused this warning; is this a bug or is there really something fundamentally wrong with my questions? Is there a minimum average score greater than 2.25 I need to aim for?

I have no intentions of asking more questions if they are not well received; ban or not, that just basic ettiquette. But I am struggling to figure out where I went wrong.