The IPv6 payload may like the following:
IPv6 Header -> ExtHeader -> ... -> UpperLayer Header
I use Scapy to make a packet such that:
IPv6 -> Hop-by-Hop-Option -> Neighbor Solicitation 
However from Sniffer, I don't see the Neighbor Advertisement response. So I try with this kind of packet:
IPv6 -> Neighbor Solicitation .
Then It's work!
Just wondering, the packet format I make in  is invalid? So the opposite station doesn't honor it??