OSPF to 2 Data Centers

[Cornelp]

I got a question:

I have 2 Data Centers, each connecting to my HQ via E-Lines. Im running OSPF, but I have a little issue.

HQ
Firewall 1 Connected to DTC1 via OSPF (working perfect)
Firewall 2 Connected to DTC2 via OSPF (working perfect)
Both Firewalls (1/2) are connected to my HQ Cisco Core.
When I try to connect my HQ Core to each Firewall (locally), OSPF only works each at the time. I cannot get them both running (ospf 1 area 0) at the same time.

Could someone tell me how would I go about this? I could provide a Topology Visio Diagram if needed.
Thanks…