Your object is a text frame.
Convert it to a graphic frame.
See menu Object > Contents > Graphic
Then the Scissors Tool will work as expected.
It could help if you change the minimum area for the pasteboard to 210 x 210 mm to see the whole frame.
You do that in the Preferences for Guides and Pasteboards.


Text frame converted to graphic frame:

Now the Scissors Tool is working as expected:

Regards,
Uwe Laubender
( ACP )