No connection with wireguard

ESPHome
1

I’m trying to connect a remote esp32 device to homeassistant.
for this i flashed the device with Wireguard enabeld.

###############################################################################
# Time
###############################################################################
time:
  - platform: sntp
    timezone: Europe/Brussel
    id: net_time

###############################################################################
# Wireguard
###############################################################################
wireguard:
  require_connection_to_proceed: true
  address: 10.5.5.2
  private_key: ******
  peer_endpoint: *****
  peer_public_key: ******
  peer_port: 51820
  netmask: 255.255.255.0
  peer_allowed_ips:
    - 0.0.0.0/24
  peer_persistent_keepalive: 25s

binary_sensor:
  - platform: wireguard
    status:
      name: 'WireGuard Status'

I checked both keys several times, but nothing works.
When loading the keys and setttings in my phone winguard client, the phone is connecting to the server.

I setup a winguard server on a decoX50

The error i get is:

[20:47:59][D][wireguard:105]: WireGuard remote peer is offline (latest handshake timestamp not available)