Unable to SSH into my proxmox hypervisor from a VM

Question

to start, here is my infra in summary :

I have a Proxmox server with an IP public, I created a vmbr1 bridge from Proxmox (192.168.0.1) and I use IP 192.168.0.108 for my VM.

Here is the route : 192.168.0.0/24 dev vmbr1 proto kernel scope link src 192.168.0.1

I deleted all iptables rules, I have this one left for NAT:

Chain POSTROUTING (policy ACCEPT 786 packets, 36868 bytes)

pkts bytes target prot opt in out source destination

707 40652 MASQUERADE all -- * vmbr0 192.168.0.0/24 0.0.0.0/0

When I try to connect in SSH from the VM 192.168.0.108 on the hypervisor it does not work. I can see packets passing through with a tcpdump.

Do you have any idea? I've been stuck on this for several days.

Thanks to you !

EDIT :

Here is /etc/network/interfaces :

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet manual
    network X.X.X.0

iface eth1 inet manual

auto vmbr0
iface vmbr0 inet static
    address X.X.X.X/24
    gateway X.X.X.1
    bridge-ports eth0
    bridge-stp off
    bridge-fd 0

iface vmbr0 inet6 static
    address X/64
    gateway X

auto vmbr1
iface vmbr1 inet static
  address 192.168.0.1
  netmask 255.255.255.0
  bridge_ports none
  bridge_stp off
  bridge_fd 0

Here is iptables -L -t nat :

Chain PREROUTING (policy ACCEPT)
target     prot opt source               destination

Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

Chain POSTROUTING (policy ACCEPT)
target     prot opt source               destination
MASQUERADE  all  --  192.168.0.0/24       anywhere