Information not saved in WPDB

I have been trying to troubleshoot a plugin that fetches data from an API and stores the data in a mysql database. The problem is that the plugin stopped storing the data a while ago. I deleted some data to free up some space, checked any and all error messages, without luck. The code that stores content in the data base is:

        $new_part_in_wpdb = array(
            'post_title'     => $truck_part_title_without_sku,  // The cleaned title
            'post_content'   => $parts_result['description'],  // The text content
            'post_name'      => $truck_part_slug,  // The name (slug)
            'post_status'    => 'publish',  // Make it live
            'post_type'      => 'part', // Define the CPT
            'post_author'    => 1 // Set an author ID
          );
        $post_id = wp_insert_post( $new_part_in_wpdb );

        update_post_meta( $post_id, 'vendor_sku', $parts_result['vendor_sku'] );

        update_post_meta( $post_id, 'part_details_json', json_encode( $part_details ) );

        wp_set_object_terms( $post_id, (int)$truck_part_tax_id, 'part_type', false );

        if (is_wp_error( $post_id )) {
            $errors = $post_id->get_error_messages();
            foreach ($errors as $error) {
              echo $error;
            }
          }

      endif;

      // Reset Post Data
      wp_reset_postdata();

The API fetch is fine and anything above the code seems to work properly. There are 18000+ posts in the database, everything in the database gets displayed properly. The cron job is set to hourly, but nothing gets saved. I am not sure if a recent WP version had anything to do with it. Any pointers would be greatly appreciated.