Course Survey ins LMS

Dear Experts,

We have following topic and don't know what is the problem.

Survey remains as OVERDUE in the system for some people and doesn't disappear. For another course after 14 days another Survey disappear. We want to define it for all if the learner don't react that the survey disappear.

But we can not find the diffrence between Survey 1 and Survey 2. Both seems to be the same.

Could somebody give us a tip what we should do?