Own field - Hyperlink doesn't work

[Wendy DS]

Hi, I added a field: 'external Document' - Type: Hyperlink.

In this field, I added the link to the external document which is saved on a SharePoint Site.

If I click on this link, an Excel file opens.
If I edit the field and copy/paste the correct Word document opens.

How is it possible that the visualized link goes to an Excel file and when I edit the field, the link points to the correct Word document?