The FIELDS = needs to be a quoted string list as in:
FIELDS = "status","message_id","message_delivered_date","message_delivered_time","service","payload"
I see that difference and Ido not have DATETIME_CONFIG = CURRENT. I would remove that setting anyway, as the docs say this about it:
DATETIME_CONFIG =
* Specifies which file configures the timestamp extractor, which identifies
timestamps from the event text.
* This configuration may also be set to "NONE" to prevent the timestamp
extractor from running or "CURRENT" to assign the current system time to
each event.
* "CURRENT" will set the time of the event to the time that the event was
merged from lines, or worded differently, the time it passed through the
aggregator processor.
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