The mount happens before the network is connected, hence is failing … Just a guess.
Difficulty: ★☆☆☆☆
Arch Wiki ) to load devices at boot time. The loading of devices is arbitrary and therefore you cannot predict which device will be available at a given path.
But static device names do exist and you can assign specific locations to your device and thus ensure e.g. scripts will work as expected.
Difficulty: ★★☆☆☆
[root tip] [How To] Use systemd to mount ANY device
Only use an automount unit if the device is not readily available at boot like removable devices and network locations.