Title: PHP Warnings in ACF Integration
Last modified: June 10, 2026

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# PHP Warnings in ACF Integration

 *  [kathylynnward](https://wordpress.org/support/users/kathylynnward/)
 * (@kathylynnward)
 * [4 days, 20 hours ago](https://wordpress.org/support/topic/php-warnings-in-acf-integration/)
 * I am experiencing an issue with the Slim SEO – ACF Integration.
   The PHP log file
   shows warnings: **Undefined array key “…”**The issue is at line 16 of src/Integrations/
   ACF/Renderer.php$field = $this->field_objects[ $name ] ?: null;If $name does 
   not exist as a key in $this->field_objects, PHP throws the warning.(The key may
   not exist in cases where the ACF field has been added to an existing post type
   but not all posts have the field set)Replacing the ternary shorthand (Elvis operator)
   with the null coalescing operator fixes the issue.$field = $this->field_objects[
   $name ] **??** null;This safely checks for existence before accessing the array
   key and prevents the warning.

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## Tags

 * [ACF](https://wordpress.org/support/topic-tag/acf/)
 * [PHP Warning](https://wordpress.org/support/topic-tag/php-warning/)

 * 0 replies
 * 1 participant
 * Last reply from: [kathylynnward](https://wordpress.org/support/users/kathylynnward/)
 * Last activity: [4 days, 20 hours ago](https://wordpress.org/support/topic/php-warnings-in-acf-integration/)
 * Status: not resolved