CB Activity

HI, I guess I have a little Problem with CB Activity. My versions are Joomla 6.0.3, CB Builder 2.11.0 and CB Activity 6.2.0. I tried to test in the profile activity stream the content preview of links, like it's possible in your demo site.
That didn' work....only the link appears (I tested the same link in the demo site, that worked). I tried to edit that entry, and in the edit view, there where the symbols of 2 media files I already deleted. I looked in the admin backend for the details of the entry. Then I switched back to backend>CB>plugin>CB Acivity>Activity Streams. Now all streams except of the profile.activity stream are deleted, or unvisible, I don't now. 

What is the problem?

Best regards Uwe 

I guess I found the problem. There where another 2 media files from 2023 left in CB Gallery. I deleted them, now the preview ist possible. But the standard activity stream like recent.activity a.s.o. are still lost. I reinstalled CB activity via web, but that didn't held.

How could I get back the standard stream? And what do I need to keep in mind because of gallery files, that this will not happens again?

Best regards Uwe