functions.php file causing intermittent outages

My site uses the Astrid theme (child theme). Beginning last Saturday, my website started intermittently crashing for 10-15 minutes at a time before then coming back online. (I receive outage alerts via Jetpack.) I checked my error log, and it includes *countless* instances of the following message:

PHP Warning: Attempt to read property “ID” on null in /home4/moviemb8/public_html/wp-content/themes/astrid/functions.php on line 269

I spoke with Bluehost, and they suggested that I change my PHP version, which had been 8.2. I changed it to 8.1, and the error recurred. I then switched it to 8.3; since then, the error has occurred only once in the past day, but the error log keeps generating the same message, so I’m concerned that the site will continue to intermittently crash in the future. (Obviously this issue is difficult to troubleshoot because the outages are intermittent, not permanent.)

Can you provide some sort of fix or update to Astrid’s functions.php file? It’s unclear to me what line 269 does, and I hesitate to mess around with the code myself.

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