DNSMasq unknown interface wifi0 - failed to start

Introduction

I am trying to use my Ubuntu Core-RaspberryPi as a Wifi Access point. Therefore, I am using hostapd and dnsmasq. I followed this tutorial in order to setup everything.

I start them manually - so all interfaces should be up and running when the services start.

HOSTAPD

My hostapd.conf file:

interface=wlan0
driver=nl80211
ssid=my_ap
hw_mode=g
channel=6
macaddr_acl=0
auth_algs=1
ignore_broadcast_ssid=0
wpa=3
wpa_passphrase=my_password
wpa_key_mgmt=WPA-PSK
wpa_pairwise=TKIP
rsn_pairwise=CCMP

I added this line to /etc/default/hostapd:

DAEMON_CONF=/etc/hostapd/hostapd.conf

DNSMASQ

I have the following dnsmasq.conf file:

interface=wlan0
dhcp-range=10.0.0.2,10.0.0.10,255.255.255.0,12h
no-hosts
addn-hosts=/etc/hosts.dnsmasq

My etc/hosts.dnsmasq file:

10.0.0.1 raspbi

My etc/network/interfaces file:

auto wlan0
iface wlan0 inet static
address 10.0.0.1
netmask 255.255.255.0

EDIT: IP Address List Logs:

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000 link/ether b8:27:eb:46:24:90 brd ff:ff:ff:ff:ff:ff inet 10.0.0.68/24 brd 10.0.0.255 scope global dynamic eth0 valid_lft 86207sec preferred_lft 86207sec inet6 fe80::ba27:ebff:fe46:2490/64 scope link valid_lft forever preferred_lft forever
3: wlan0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN group default qlen 1000 link/ether b8:27:eb:13:71:c5 brd ff:ff:ff:ff:ff:ff

What I get

If I then try to start my dnsmasq by running systemctl start dnsmasq I get an error "unknown interface wlan0".

EDIT: What I tried

I also tried to force start wlan0 by running sudo ifconfig up wlan0 but still get the same error message

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