Hi Emilia,
Whenever you see an odd behavior or error in the DSpace 7 User Interface, your first step should be to look for a possible underlying error message using the
Troubleshooting guide. The underlying error message may occur in your browser's DevTools, or it may be in the backend logs. Just follow the steps in that guide to see what you can find.
My best guess here is that some underlying error message is occurring. But, it's impossible to help further without finding the underlying error...as that error will provide details about *why* this problem is occurring, and whether it's a misconfiguration or bad data or possibly even a bug.
Tim