I did a really dummy thing to check the consequences; I clicked "disconnect" next to my Android device on the Wi-Fi page in LuCI. Even restarting the Wi-Fi didn't helped to get me back, so I was wondering how can I unban myself?
Sorry for being idiot but I really tried to google it and didn't found anything, Not even in the iw documentation...
I think I found it, it's in hostapd. I'll learn it and avoid stupid mistakes in the future 
Strange. Others may please correct me, but to my knowledge, the “Disconnect” button does not store bans or hold blacklists; it just causes a single disconnect instruction (deauthentication/disassociation) to be sent from your AP (hostapd) to your client.
So, to my knowledge, it’s entirely up to your Android device to interpret the disconnection request as a “please don’t come back” or not in the first place.
I’m running 6 APs here, all at current 24.10.4. When I “Disconnect” some of my devices, they all behave slightly differently.
Some switch between 2 APs. When I push disconnect on the first, they connect to the second; when I push disconnect on the second, they resume back to the first. But they never stay disconnected and reconnect to another AP immediately.
Some switch between 3 APs, basically the same as before but using a third AP in their cycle.
Some just disconnect, don’t reconnect immediately, but resume back to the one AP I just kicked them from after a couple of minutes.
I assume it’s either the client operating system or the client driver, but I’m fairly certain there’s no “ban list” on the OpenWrt side.