SD-RED 60 with SG 210 (HA)

Hello Community,

after a connection loss of our internet connection, we have issues with a SD-RED 60.

it connects, but shortly after this it dissconnects with "RUNTIME_ERROR_OCCURRED, Unstable peers"

Log:

2022:09:01-04:50:32 sophos-1 red_server[15934]: SELF: New connection from <RED WAN IP> with ID <REDID> (cipher AES256-GCM-SHA384), rev1
2022:09:01-04:50:32 sophos-1 red_server[15934]: <REDID>: connected OK, pushing config
2022:09:01-04:50:33 sophos-1 red_server[15934]: <REDID>: command '{"data":{"version":"0"},"type":"INIT_CONNECTION"}'
2022:09:01-04:50:33 sophos-1 red_server[15934]: <REDID>: Initializing connection running protocol version 0
2022:09:01-04:50:33 sophos-1 red_server[15934]: <REDID>: Sending json message {"data":{},"type":"WELCOME"}
2022:09:01-04:50:34 sophos-1 red_server[15934]: <REDID>: command '{"data":{},"type":"CONFIG_REQ"}'
2022:09:01-04:50:34 sophos-1 red_server[15934]: <REDID>: Sending json message {"data":{"pin":"","fullbr_dns":"<Sophos SG IP>","split_networks":"<Sophos SG Network>/24<Sophos SG Network 2>/24 1.2.3.4 <Sophos SG VPN Client Network>/24 <Sophos RED Remote Network>/24","lan2_vids":"","lan4_vids":"","local_networks":"","tunnel_id":1,"manual2_netmask":24,"asg_cert":"[removed]","manual_address":"0.0.0.0","bridge_proto":"none","unlock_code":"ap34hun2","password":"","manual2_defgw":"0.0.0.0","prev_unlock_code":"","manual_netmask":24,"lan3_vids":"","mac_filter_type":"none","mac":"<MAC>","dial_string":"*99#","manual2_address":"0.0.0.0","manual_dns":"0.0.0.0","poe_port1":0,"poe_port2":0,"lan1_mode":"unused","username":"","activate_modem":0,"tunnel_compression_algorithm":"lzo","fullbr_domains":"<domains>","htp_server":"<SG WAN A-Record 1>","uplink_balancing":"failover","asg_key":"[removed]","version_red60":"1-1176-7ef037314-b1551d2","type":"red60","deployment_mode":"on...L1525
2022:09:01-04:50:38 sophos-1 red_server[15934]: <REDID>: command '{"data":{"key1":"qfIqc9BGOY7q25KWYpPHFV1741LU8VN9AeUySJ\/y\/BY=","key0":"BMLgCa5Gzv69i68Sd433jEAiNQgJYAKrGs6QZDucOkc=","key_active":0},"type":"SET_KEY_REQ"}'
2022:09:01-04:50:38 sophos-1 red_server[15934]: <REDID>: Sending json message {"data":{},"type":"SET_KEY_REP"}
2022:09:01-04:50:39 sophos-1 red_server[15934]: <REDID>: command '{"data":{"seq":0},"type":"PING"}'
2022:09:01-04:50:39 sophos-1 red_server[15934]: id="4201" severity="info" sys="System" sub="RED" name="RED Tunnel Up" red_id="<REDID>" forced="0"
2022:09:01-04:50:39 sophos-1 red_server[15934]: <REDID>: Sending json message {"data":{"seq":0},"type":"PONG"}
2022:09:01-04:50:40 sophos-1 red_server[15934]: <REDID>: command '{"data":{"wan2_ip":"<RED WAN IP 1>","wan1_ip":"<RED WAN IP 2>","uplink":"WAN1","uplink_state":"1"},"type":"STATUS"}'
2022:09:01-04:50:55 sophos-1 red_server[15934]: <REDID>: command '{"data":{"seq":1},"type":"PING"}'
2022:09:01-04:50:55 sophos-1 red_server[15934]: <REDID>: Sending json message {"data":{"seq":1},"type":"PONG"}
2022:09:01-04:51:12 sophos-1 red_server[15934]: <REDID>: command '{"data":{"message":"Unstable peers","type":"RUNTIME_ERROR_OCCURRED"},"type":"DISCONNECT"}'
2022:09:01-04:51:12 sophos-1 red_server[15934]: <REDID>: Disconnecting: RUNTIME_ERROR_OCCURRED, Unstable peers
2022:09:01-04:51:12 sophos-1 red_server[15934]: id="4202" severity="info" sys="System" sub="RED" name="RED Tunnel Down" red_id="<REDID>" forced="1"

I have tried:

- enable/disable the RED

- change the unified firmware to 0 (and back because it didn't help)

I have openend a case with support, but maybe someone else have problems or a solution.

At the Moment i wont delete the RED, because i read about someone else had tried this, but had to reset the RED to get it working again. But i can't physically reach the RED, because its about 500 kilometers away.

any ideas?