I can't reproduce this, and I have to think that's a pretty major flaw to get through internal QA before it ever gets to end users.
Can you provide more details about the problem?
It is every time? some times?
Is there something specific about the formulas in use?
Does it happen on new documents? or old ones? or both?
macOS Tahoe isn't beta any more. I could just about, possibly, kinda-sorta see how this might happen in beta, but we're past that.
Are you sure you're using Copy/Paste, and not Copy Snapshot or Paste Formula Results (the latter options will copy or paste the current values of the selection, not their underlying formulae). Are you using menus or key commands (just trying to eliminate some kind of keyboard override on the commands).