I have similar with a Samsung S23 Ultra. From "cold" always connects first time via wireless. But won't automatically reconnect when "warm" (after a few minutes to an hour or so). I have found that toggling bluetooth on the phone (off then on) seems to clear the issue and it reconnects. Irritating and I'm hoping an updated will fix in due course.
Not able to find the second rubber insert. But I do have a tidy garage now! 😀
I didn't actually use the strips at all. With a wider flush mount roof box there would likely be enough in a single strip to cut for either side of the box. Replacement strips are also available for less than £10 on eBay.
Good question Gareth. I have found one in my garage (unused and uncut), and the original printed instruction manual. I'll rummage in the garage some more this afternoon and post an update if I find the other.