Meta description content empty

About the function:
“function gretathemes_meta_description()”

For the option:
“if (is_singular())”

My return is supposed to be:
echo ‘<meta name=”description” content=”‘ . $des_post . ‘” />’ . “\n”;

But the result in my code has an EMPTY CONTENT, like so:
<meta name=”description” content>

Is there something else I can use for a meta description on a single page instead of “. $des_post ” to fix this? I am wondering if this is something that has been updated on version 5.8.3 (which is what I have).

Thank you

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