Canvas graded survey has a bug?

[htdinh]

I gave my class a graded survey, but many students didn't get full credit even though they answered every question in the survey. Then I checked a question that a student answered but received no credit for it. I notice that there are two answer choices in that question that are not grayed out (see screenshot). Does this mean that to get credit for a multiple-choice question in a graded survey, the student must not change their selection? 

[awilliams]

Hi,  @htdinh . When you look at the grades in the Gradebook or on the right-hand side of SpeedGrader does it show less than full value?

[Stef_retired]

 @htdinh ‌, do you still need assistance with this?