Data path for both IPv4 and IPv6 extra route not working

1. Create N1 with S1(ipV4) and S2(ipv6) and N2 wit S1(IPv4) and S2(IPv6)
2. Boot All VM's
3. Create router(R1) and associate both IPv4 and IPv6 subnets from both Network  to it.
4. Verify ping across all VM's for both IPv4 and IPv6.
5. Dissociate all subnet from Router and associate back.
6. Repeat step 5 for minimum 5 times.