OSPF state moves from Established to Down, when the keep-alives are missing. In your case, the state is 2 Way and not Down, which means the Hello packets are not missing but the next packets (dbd) packets are lost in transit or the MTU configuration you have applied is not getting into efffect.
Do you use GRE or some other type of interface? If so, we can try applying the MTU configuration on the specific interface and check.
Please take a pcap for OSPF (use filter protocol 89 to capture the OSPF packets only ) from both Hub and Spoke device during problem state.
- Have you found a solution? Then give your helper a "Kudos" and mark the solution.
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