Warning filter_input() expects parameter 3 to be int

I am getting the following warnings on my site:
Use of undefined constant ILTER_SANITIZE_SPECIAL_CHARS – assumed ‘ILTER_SANITIZE_SPECIAL_CHARS’ (this will throw an Error in a future version of PHP) in /wp-content/plugins/elastic-email-sender/class/ees_mail.php; on line 140
filter_input() expects parameter 3 to be int, string given in <b>/wp-content/plugins/elastic-email-sender/class/ees_mail.php; on line;140&

• This topic was modified 5 years, 5 months ago by garikaib.
• This topic was modified 5 years, 5 months ago by garikaib.

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