sophos UTM9 SG125 & CISCO SG200-26 26-Port Gigabit Smart Switch 1gB connection

Hello Support, 

We have a Sophos SG125 with on ETH1 configured our External (WAN). It is connected to our CISCO SG200-26 26-Port Gigabit Smart Switch but unfortunately, I can't get it configured to a 1GB speed connection. 

Settings for eth1:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: Symmetric
Supports auto-negotiation: Yes
Advertised link modes: 100baseT/Full
Advertised pause frame use: Symmetric
Advertised auto-negotiation: Yes
Speed: 100Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 1
Transceiver: internal
Auto-negotiation: on
MDI-X: on (auto)
Supports Wake-on: pumbg
Wake-on: g
Current message level: 0x00000007 (7)
drv probe link
Link detected: yes

When changing it to 1gb it breaks. 

gatekeeper:/root # ethtool -s eth1 autoneg off speed 1000 duplex full
gatekeeper:/root # ethtool eth1
Settings for eth1:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supported pause frame use: Symmetric
Supports auto-negotiation: Yes
Advertised link modes: 1000baseT/Full
Advertised pause frame use: Symmetric
Advertised auto-negotiation: Yes
Speed: Unknown!
Duplex: Unknown! (255)
Port: Twisted Pair
PHYAD: 1
Transceiver: internal
Auto-negotiation: on
MDI-X: on (auto)
Supports Wake-on: pumbg
Wake-on: g
Current message level: 0x00000007 (7)
drv probe link
Link detected: no

Could you give me some advise how to get the connection on 1gb?

Kind Regards,

Michel Wigbers