Wireless Access

I'm deploying a network which consists of 20 APs (303) some 1920s switches and 7030 controller. For now I've managed to configure everything correctly and 17 out of 20 APs are running. The problem is 3 APs are in booting state all the time. The green light is blinking on system status led. What suprises me- it has the correct IP address (assigned by controller) but I can't use SSH or http/https to connect to it. I see it when scanning the environment, I can ping it but every time I want to connect to it, it says "Connection refused". It's not in IAP mode, there's no "SetMeUp" network. I can't use console cable to connect to it because it's already mounted on the celling, 10 meters above me. Any idea what to do/what can cause it?

EDIT: I forgot to mention it but it obviously doesn't show on 7030 controller provision table.

Did you try typing "show log system 100" or "show ap database" on the 7030 to see if there is any information about those APS?

Yes, there's no information about any of these 3. I think there's something wrong with the APs config which causes them to reset and bootloop so I'll probably end up forced to factory reset them. There is probably no other way to do it other than using "reset hole", is there?

Are you running at least 8.3.0.0 on your MDs?  That is the minimum for the AP303 https://www.arubanetworks.com/assets/ds/DS_AP303Series.pdf

I'm running 8.6.0.4.

I would open up a technical support case.  There is not enough information to figure out what is wrong.