I have regularly the situation that someone does not finish his survey, so it stays pending. (I cannot upload/add media, as this goes into an error, see https://i.imgur.com/4ABYdbc.png )
I do see that most of the survey has been filled, it is a genuine person, but they have forgotten to Push the Finish button. 
Is there a possibility to force the survey to finished, so the responses that are there still can be used in a report?