when it comes to focusing components between open/active states you need to wrap the focus setter around a setTimeout with a very small delay, so your code should look something like this:

useEffect(() => {
  if (commandRef.current) {
    setTimeout(() => {
      commandRef.current.focus();
    }, 50)
  }
}, []);

if you're trying to highlight a CommandItem component, you'll want to set the data-selected attribute alongside the focus, which looks something like this:

useEffect(() => {
  if (commandItemRef.current) {
    setTimeout(() => {
      commandItemRef.current.setAttribute("data-selected", "true")
      commandRef.current.focus();
    }, 50)
  }
}, []);