Global Administrator delete form of person no longer with the company

I have a form that was created by a person who is no longer with the company.  I am a global admin and was presented this link (altered) and it opens up yet 

https://forms.office.com/Pages/ResponsePage.aspx?id=0HNNoRiVXoP9LUSNNoR9fGI3DrNNoRNNoRNNoRNNoRD 

I can't get to https://forms.office.com/Pages/DesignPageV2.aspx?subpage=design&FormId= (put ID here)

https://forms.office.com/Pages/DesignPageV2.aspx?origin=NeoPortalPage&subpage=design&id=

How do I ensure that this form is REMOVED from the system?  It seems that even as a Global Administrator I am not able to take action and this will cause problems as people have the link and filling out the form.