Few IPv4 entries are missing in FIB and none of the IPv4 address gets advertised to DC-GW

Few IPv4 entries are missing in FIB and none of the IPv4 address gets advertised to DC-GW

1. Topology -> N1,S1(IPv4) &S2(IPv4), with 2 ports on each subnet and boot the VM's.
2. Create Router and add both the subnets to Router. --> PASS
3. Create L3VPN and Associate Router to it. --> PASS
4. Try to remove IPv4 subnet and add it back to Router  around 5 times and  validate FIB appearing and dis-appearing properly in flows in DC-GW. --> some time FAILS.
5. Add back all the subnet to Router where Router is part of L3VPN. --> PASS
6. Delete L3VPN
7. Create L3VPN and add router back. --> FAILS.