AR9462 still not working properly

Hello, everyone. I have been using Dell 1901 (AR9462) wireless card since release 12.2, but minor problems keep occuring. For example, it cannot be recognized in bsdconfig, when not connected to networks, error message “Failed to add operating class IE” repeates. I remembered someone has told me that he would deal with that.
Now, I have done a brand-new installation of 12.3. But bsdinstall still had diffculty in scanning Wi-Fis, and after I had tried a few times, no Wi-Fi could be found at all. How to deal with this? I have put up a PR about that. I’m sorry for that I may have described the problem unclearly there. And is there any information I need to provide?