Unable to Proceed with PPR from "Missing payment conversion rates"

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There are instances where daily rates are not uploaded for 'today' and the payment process request ends up in the status "missing payment conversion rates". We will upload daily rates, then run Apply Missing Conversion Rates. However, the PPR remains in the same status and when attempting to hit submit, an error pops up "You can't lock this record because it's already locked by another user."

I can confirm it's all the same Business Unit, so I would expect the scheduled process to update the PPR with rates allowing us to submit.