How to notify errors through td-agent immediately, only sending counts of certain acknowledged errors daily.

td-agent.conf

# Retrieve Error Log
<source>
  type tail
  path {{ path }}
  format multiline
  format_firstline /^\d{4}-\d{2}-\d{2}/
  format1 /^(?<text>.*)/
  tag raw.app.errorlog.{{ hostname }}
  pos_file /var/tmp/app_log.pos.slack
</source>

# Filter Acknowledged Error
<match raw.app.errorlog.{{ hostname }}>
  type rewrite
  add_prefix filtered
  <rule>
    key           text
    pattern       FileNotFoundException
    append_to_tag true
    tag           FileNotFoundException
  </rule>
</match>

# Notify Error to the Slack channel
<match filtered.raw.app.errorlog.{{ hostname }}>
  type slack
  webhook_url {{ webhook_url }}
  channel {{ channel }}
  username ERROR_NOTIFIER
  message '{{ td_agent_app_errorlog_mention }}```[host] {{ hostname }} [Path] {{ errorlog_path }}``` %s'
  message_keys text
  color warning
  flush_interval 10s
</match>

# Notify the count of Acknowledged Errors filtered above
<match filtered.raw.app.errorlog.{{ hostname }}.FileNotFoundException>
  type grepcounter
  count_interval 86400 # = 24 hours
  input_key text
  threshold 1
  add_tag_prefix count
</match>
<match count.filtered.raw.app.errorlog.{{ hostname }}.FileNotFoundException>
  type slack
  webhook_url {{ webhook_url }}
  channel {{ channel }}
  username EXISTING_ERROR_NOTIFIER
  icon_emoji :admission_tickets:
  message_keys count
  message '```FileNotFoundException occured %s times within this 24 hours at {{ hostname }}```'
  color #FFB6C1
  flush_interval 10
</match>