lab: I have a [0/0] buffer space on my CP shell but on my worker shell I have plenty

As the topic states, when trying to select (copy) anything on my cp (control plane) shell I get a [0/0] in the top right hand corner and nothing is copied though the yellow selection works. In my worker shell it works just fine, it shows [0/1116].

I copied a single IP address (on the worker tab) and now nothing I select and (try to) copy works anymore.

What is causing this behaviour and how to solve this?