My ISP is Unity Media, config for IPV6 as below. IPv4 is a fixed address. IGMP and IPTV are off. (were never on)

The options are all available in the router. However no client machine gets an ipv6 anymore. In the previous firmware version, with the same settings does give an ipv6 address to all client machines....

Model : Hardware Version : Firmware Version : ISP : For the TP-Link Archer C9 V1, the beta firmware 150908_beta, does not allow/work with SLAAC I reverted back to firmware version 150811 as that one...