RPI acces point shutsdown (VNC)

Hello. I have a raspberry pi 3, where i have kali Linux installed and i used the build in wifi card as a hotspot adapter, so i can connect with my phone and use VNC. I also have a wifi usb adapter, so i can connect to other hotspots etc. But when i disconnect from a hotspot or plug the usb adapter off, my wlan0 hotspot goes offline (which means my VNC server also gets offline) and i have to reset my rpi.

So what can i do to fix this?

Thanks.

There might be something to disable management of a specific interface somewhere but you'll have to google it, I can't remember where.

What I would do is disable network manager and do stuff manually. Have hostapd running for your AP and use wpa_supplicant to connect to access points.