[CAUSE] The tmnxVRtrPdnAddrMismatch notification is generated when the IP address learned by the PDN interface through the cellular network could not be installed on the PDN router interface. For IPv4, this occurs when the parent interface has a mismatching configured IP address or when the learned PDN IP address overlaps another IP address in the router instance. The notification will only be generated when the PDN interface is set unnumbered to the system interface or any other existing loopback interface. For IPv6 operation, this occurs when the IPv6 address has a mismatching subnet to the address configured for the PDN router interface or if the exact same IPv6 address is configured on the PDN interface as the address received by the network. [EFFECT] The PDN Interface will be operationally down. [RECOVERY] Check the configured IP address for the PDN interface or parent interface, check the other IP addresses in the router instance, and/or check the state of the cellular network.