Filebeat is not closing files and open_files count keeps on increasing

Please find the yaml files.

/etc/filebeat/filebeat.yml:::

filebeat.config:
  inputs:
    enabled: true
    path: inputs.d/*yml
    reload.enabled: true
    reload.period: 10s
setup.template.settings:
  index.number_of_shards: 1

/etc/filebeat/inputs.d/modulename.yml::::

- type: log
  paths:
    - /modulename.log
  scan_frequency: 10s
  fields:
    service: modulename
    env: dev
  multiline.type: pattern
  multiline.pattern: ^\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}.\d{3}
  multiline.negate: true
  multiline.match: after
  close_inactive: 1m
  close_removed: true
  clean_removed: true

Can you please explain more on your comments about multiline never close. How can I check that?