Fast charging BMW i4 at public charging stations is a great advantage for electric vehicle owners. These charging stations operate using three-phase DC, which is why they allow for fast charging. It's been reported several times by BMW i4 owners that one fast charging wallbox is working properly, while another nearby isn't. The first thought is that the station that isn't charging is faulty, and the charging issue is only temporary. It would be best to replace the station, and the problem may be solved. The most natural and obvious solution is to try a different wallbox or a different place, hoping that the "unable to charge" or "charging unavailable" message no longer appears on the vehicle's display. If this also fails, there may be a different issue that requires a thorough evaluation and possibly a software update.