1. Adjust BGP prepend on both router, increase on Lumen and remove prepend on Cogent router.
CL-9300-ISP1-LUMEN#
route-map CL-OUT-S-RMAP permit 10
match ip address prefix-list CL-INTERNET-OUT-PL
set as-path prepend 32607 32607 32607 32607 32607
route-map CL-OUT-P-RMAP permit 10
match ip address prefix-list CL-INTERNET-OUT-PL
set as-path prepend 32607 32607 32607 32607 32607
CL-9300-ISP2-COGENT#
route-map COGENT-OUT-RMAP permit 20
match ip address prefix-list CL-PREFIX-OUT-PL
no set as-path prepend 32607 32607
2. Adjust HSRP priority for interface vlan 999
CL-9300-ISP1-LUMEN#
interface Vlan999
standby 1 priority 100
CL-9300-ISP2-COGENT#
leave standby priority at 120