Interface Gi0/0.3200 is connected to ISP and is in VRF C1:
interface GigabitEthernet0/0.3200 encapsulation dot1Q 3200 ip vrf forwarding C1 ip address a.b.232.90 255.255.255.224 ip nat outside ip virtual-reassembly in end
#sh arp vrf C1 Protocol Address Age (min) Hardware Addr Type Interface Internet a.b.232.65 0 001e.be75.7c78 ARPA GigabitEthernet0/0.3200 Internet a.b.232.90 - 78da.6e31.edf0 ARPA GigabitEthernet0/0.3200
Interface Gi0/1.3200 is also connected to ISP and is in Global routing table.
interface GigabitEthernet0/1.3200 encapsulation dot1Q 3200 ip address a.b.232.94 255.255.255.224 no ip proxy-arp no cdp enable end
When interface Gi0/1.3200 is UP interface Gi0/0.3200' IP Address a.b.232.90 (which is in VRF C1) also appears in Global routing table.
sh ip route
a.0.0.0/8 is variably subnetted, 3 subnets, 2 masks C a.b.232.64/27 is directly connected, GigabitEthernet0/1.3200 L a.b.232.90/32 is directly connected, GigabitEthernet0/1.3200 L a.b.232.94/32 is directly connected, GigabitEthernet0/1.3200
Mac address of a.b.232.90 is also in both VRF C1 and in GR so C1 connection is lost.