Plugin provokes a PHP warning

The plugin provokes the following PHP warning.

( ! ) Notice: Function WP_Scripts::localize was called <strong>incorrectly</strong>. The <code>$l10n</code> parameter must be an array. To pass arbitrary data to scripts, use the <code>wp_add_inline_script()</code> function instead. Please see <a href="https://ww.wp.xz.cn/support/article/debugging-in-wordpress/">Debugging in WordPress</a> for more information. (This message was added in version 5.7.0.) in **WEBROOT**/wp-includes/functions.php on line 5831