When configuring OSPF in a VRF for Customer routes you need to be aware that the VRF will create the OSPF instance as an ABR (Area Boarder Router)
When OSPF is configured in a VRF it will be created as an ABR.
This may prevent summary and external routes from being put in the VRF routing table when OSPF is not part of Area 0
For example if you configure the VRF with OSPF area 1 and you have other customer routers that are ABR with an interface in area 0.
The summary and external routes from area 0 will not get put in the VRF routing table.
Solution 1: You will need to put the OSPF instance in Area 0 and make sure one of the interfaces in the VRF is part of OSPF area 0
Solution2: If possible, make the routing-instance a Virtual Router, leaving the OSPF area set to area 1