UiPath stop working abruptly

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1

Hi,

We have a robot which schedule on Orchestrator and its working fine last 3 - 4 month
But Yesterday , robot start and after start it abruptly stop.
So we check Windows logs - Application and found below error :

{“message” : “SingleR - Failed to Parse notification Invalid notification”, “level” : “Error”, “timestamp”:“2018-01-09”}

Why this error will be occurred any idea???

Thanks,
Sandy