Hetzner /64 IPv6 subnet connection error

[NicklasM]

Good day,
I want to use my /64 IPv6 subnet on my Hetzner server for my virtual servers. I have the problem that the virtual machine can not reach the internet; I keep getting the following error message:

root@mail:~# ping 1.1.1.1
ping: connect: Network is unreachable

Spoiler: Host configuration

source /etc/network/interfaces.d/*

auto lo
iface lo inet loopback
iface lo inet6 loopback

auto eno1
iface eno1 inet static
address 95.217.75.45/26
gateway 95.217.75.1
pointopoint 95.217.75.1

iface eno1 inet6 static
address 2a01:4f9:4a:1a89:4040:394c:c6b7:5128/64
gateway fe80::1
up sysctl -p

auto vmbr0
iface vmbr0 inet6 static
address 2a01:4f9:4a:1a89:be9e:fad0:499f:91ec/64
bridge-ports none
bridge-stp off
bridge-fd 0
up ip -6 route add 2a01:4f9:4a:1a89::/64 dev vmbr0

Spoiler: Guest configuration

auto lo
iface lo inet loopback
iface lo inet6 loopback

iface vmbr0 inet6 static
address 2a01:4f9:4a:1a89:9bd2:2150:cef3:4c77
netmask 64
gateway 2a01:4f9:4a:1a89:be9e:fad0:499f:91ec/64

With kind regards