Your on-premises data center has 2 routers connected to your Google Cloud environment through a VPN on each router. All applications are working correctly; however, all of the traffic is passing across a single VPN instead of being load-balanced across the 2 connections as desired.
During troubleshooting you find:
* Each on-premises router is configured with a unique ASN.
* Each on-premises router is configured with the same routes and priorities.
* Both on-premises routers are configured with a VPN connected to a single Cloud Router.
* BGP sessions are established between both on-premises routers and the Cloud Router.
* Only 1 of the on-premises router's routes are being added to the routing table.
What is the most likely cause of this problem?