Long text with the option Rich text formatting

I have created several columns. Of these, also “Long text” with the option “Rich text formatting”.
I then entered text in the fields.
In the overview, all fields are filled and look fine.
If I now open a cell “Expand row” the content is gone.
The same happens with all fields of this type when I open the whole record. All contents at at “Long Text” with the option “Rich Text Formatting” are empty.
What is the problem ?
Can someone help ?

Thanks
Greetings
Uwe Dauer