It is because port 53 is already in use
Jun 23 18:12:02 m0054 dnsmasq[3420]: failed to create listening socket for port 53: Address already in use Jun 23 18:12:02 m0054 dnsmasq[3420]: FAILED to start up Jun 23 18:12:02 m0054 systemd[1]: dnsmasq.service: Control process exited, code=exited status=2 Jun 23 18:12:02 m0054 systemd[1]: dnsmasq.service: Failed with result 'exit-code'. Jun 23 18:12:02 m0054 systemd[1]: Failed to start dnsmasq - A lightweight DHCP and caching DNS server.