Neo4j Db unavailable

Hi Folks - So I had a neo4j db which i was using to create small nodes and relationships and then I tried to run a APOC load procedure(which handles 400000 records) to create nodes from it. However, it ran into out of heapspace issue and then later something like below.

ERROR Client triggered an unexpected error [Neo.DatabaseError.Transaction.TransactionCommitFailed]: Could not apply the transaction to the store after written to log, reference 0b22c877-5f27-4cbb-b65a-72e9e39f8521.

Now When i tried restarting my db - it throws an error like this. Any idea what could be possibly wrong? Happy to provide more details if needed.