IPV6 CMTS and DHCP Configuration

Hi, i've set up a lab with a UBR10k, a ISC DHCPv6 server, and i'm using modems Ubee DW3201B, i'm having trouble getting it workin. the modem get stuck on init6(a), my dhcp is sending relay-reply messages to the cmts, and the cmts is sending the advertise messages to the modem, but it doesn't seem to work.

my CMTS config
interface Bundle8
no ip address
cable arp filter request-send 3 2
cable arp filter reply-accept 3 2
ipv6 address 2803:3640:100:8::5/64
ipv6 enable
ipv6 nd prefix default no-advertise
ipv6 nd managed-config-flag
ipv6 nd other-config-flag
ipv6 nd ra interval 5
ipv6 dhcp relay destination 2803:3640:100:1::32

and the DHCP

option space docsis code width 2 length width 2 hash size 17;
option docsis.tftp-servers code 32 = array of ip6-address;
option docsis.cablelabs-configuration-file code 33 = text;
option docsis.cablelabs-syslog-servers code 34 = array of ip6-address;
option docsis.device-id code 36 = string;
option docsis.time-servers code 37 = array of ip6-address;
option docsis.time-offset code 38 = signed integer 32;
option vsio.docsis code 4491 = encapsulate docsis;

subnet6 2803:3640:100:1::/64{
}

subnet6 2803:3640:0100:8::/64{
range6 2803:3640:0100:8::10 2803:3640:0100:8::100;
option dhcp6.name-servers 2001:4860:4860::8888;
#prefix6 2803:3640::/56;
option docsis.cablelabs-syslog-servers 2803:3640:100:1::32;
option docsis.time-servers 2803:3640:100:1::32;
option docsis.time-offset 28800;
option docsis.cablelabs-configuration-file "/tftpboot/100_100.cm";

}