I'm doing a NAT64 translation on cisco routeur. The translation from IPv6 to IPv4 work but the return isn't translated neighter int the NAT64 statistics.
config:
interface GigabitEthernet0/1
nat64 enable
ipv6 address 2001:2525:3164:1000::1/64
interface GigabitEthernet0/0/0
ip address 194.10.83.2 255.255.255.248
nat64 enable
nat64 v4 pool pool1 194.10.83.2 194.10.83.2
nat64 v6v4 list nat64ACL pool pool1 overload
ipv6 access-list nat64ACL
permit ipv6 2001:2525:3164:1000::/56 any
Translation table:
RM_A0.1#sh nat64 translations
Proto Original IPv4 Translated IPv4
Translated IPv6 Original IPv6
--------------------------------------------------------
icmp 194.10.83.1:1 [64:FF9B::C20A:5301]:1
194.10.83.2:1 [2001:2525:3164:1000:6188:82D:86F8:708E]:1
tcp 194.10.83.1:23 [64:FF9B::C20A:5301]:23
194.10.83.2:60531 [2001:2525:3164:1000:6188:82D:86F8:708E]:60531
Total number of translations: 2
statistics:
Number of packets translated by stateless NAT64:
Packets translated (IPv4 -> IPv6): 0
Packets translated (IPv6 -> IPv4): 0
Number of packets translated by stateful NAT64:
Packets translated (IPv4 -> IPv6): 0
Packets translated (IPv6 -> IPv4): 75
Global Statistics
Prefix: 64:FF9B::/96
Packets translated (IPv4 -> IPv6): 0
Packets translated (IPv6 -> IPv4): 20
Packets dropped: 0
Wireshark capture on ipv4 network: 
on the IPv4 network everything looks fine. Any idea?
edit: that's the whole configuration of the router:
Current configuration : 2039 bytes
!
version 15.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname RM_A0.1
!
boot-start-marker
boot-end-marker
!
enable password emf
!
no aaa new-model
memory-size iomem 15
!
ip cef
ipv6 unicast-routing
ipv6 dhcp pool myPool
dns-server 2001:4860:4860::8888
domain-name Baldi.local
!
ipv6 cef
multilink bundle-name authenticated
!
cts logging verbose
!
license udi pid CISCO1921/K9 sn FCZ1918C2N2
!
vtp domain emf
vtp mode transparent
vtp version 2
!
redundancy
!
interface Embedded-Service-Engine0/0
no ip address
shutdown
!
interface GigabitEthernet0/0
no ip address
duplex auto
speed auto
ipv6 address FE80::1:1:0 link-local
ipv6 address 2001:2525:3164:100F::/127
ipv6 ospf 99 area 0
!
interface GigabitEthernet0/1
no ip address
duplex auto
speed auto
nat64 enable
ipv6 address FE80::1:1:1 link-local
ipv6 address 2001:2525:3164:1000::1/64
ipv6 nd other-config-flag
ipv6 dhcp server myPool
ipv6 ospf 99 area 0
!
interface GigabitEthernet0/0/0
ip address 194.10.83.2 255.255.255.248
duplex auto
speed auto
nat64 enable
!
interface Serial0/1/0
no ip address
shutdown
clock rate 2000000
!
interface Serial0/1/1
no ip address
shutdown
clock rate 2000000
!
router ospfv3 99
router-id 0.0.0.1
!
address-family ipv6 unicast
exit-address-family
!
router rip
version 2
network 194.10.83.0
!
ip forward-protocol nd
!
no ip http server
no ip http secure-server
!
!
nat64 v4 pool pool1 194.10.83.2 194.10.83.2
nat64 v6v4 list nat64ACL pool pool1 overload
!
ipv6 access-list nat64ACL
permit ipv6 2001:2525:3164:1000::/56 any
!
control-plane
!
line con 0
line aux 0
line 2
no activation-character
no exec
transport preferred none
transport output pad telnet rlogin lapb-ta mop udptn v120 ssh
stopbits 1
line vty 0 4
password emf
login
transport input none
!
scheduler allocate 20000 1000
ntp server 2001:2525:3164:1F::
!
end