Nighthawk D8500 bug in code url http://192.168.0.1/LAN_lan.htm

Getting 400 Bad Request on the lan page, using Google DevTools I see this in the Post


Request URL: http://192.168.0.1/lan.cgi?id=bfe4f21230c496e66923478aa3157fdc632126c3
Request Method: POST
Status Code: 400 Bad Request
Remote Address: 192.168.0.1:80
Referrer Policy: no-referrer-when-downgrade
Content-type: text/html
x-frame-options: SAMEORIGIN
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9
Accept-Encoding: gzip, deflate
Accept-Language: en-GB,en-US;q=0.9,en;q=0.8
Authorization: Basic YWRtaW46RW5nIyEhMDU0NjM=
Cache-Control: max-age=0
Connection: keep-alive
Content-Length: 891
Content-Type: application/x-www-form-urlencoded
Cookie: XSRF_TOKEN=1222440606
Host: 192.168.0.1
Origin: http://192.168.0.1
Referer: http://192.168.0.1/LAN_lan.htm
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/84.0.4147.135 Safari/537.36
id: bfe4f21230c496e66923478aa3157fdc632126c3
action: Apply
device_name: Router
sysLANIPAddr1: 192
sysLANIPAddr2: 168
sysLANIPAddr3: 0
sysLANIPAddr4: 1
sysLANSubnetMask1: 255
sysLANSubnetMask2: 255
sysLANSubnetMask3: 255
sysLANSubnetMask4: 0
rip_direction: 1
sysRIPVersion: Disabled
dhcp_server: dhcp_server
sysPoolStartingAddr4: 2
sysPoolFinishAddr4: 254
select: -1
arp_enable: disable
ipmac_token: 3
dev_name: D8500
lan_ipaddr: 192.168.0.1
lan_netmask: 255.255.255.0
rip_enable: 0
rip_multicast: 1
rip_version: 2
lan_proto: dhcp
dhcp_start: 192.168.0.2
dhcp_end: 192.168.0.254
dhcp_start_old: 192.168.0.2
dhcp_end_old: 192.168.0.254
pptp_wan_ipaddr: ...
l2tp_wan_ipaddr: ...
pppoe_wan_ipaddr: ...
pptp_serv_ipaddr: 10.0.0.138
l2tp_serv_ipaddr:
wan_dns1_pri:
wan_dns1_sec:
wan_proto: pppoe
wan_ipaddr: 110.174.122.7
wan_netmask: 255.255.255.255
repeater: 0
repeater_an: 0
dlna_autoip_en: 0
tmp_lan_ipaddr: 0.0.0.0
tmp_lan_netmask: 0.0.0.0
tmp_lan_proto: null
tmp_rip_enable: null