src/properties/class-papi-property-group.php
public function format_value( $value, $slug, $post_id ) {
		if ( ! is_array( $value ) ) {
			return [];
		}

		// Fixes issue when flexible and repeater are used with group property
		// cache since we use repeaters format value function that cache values.
		// At this point the value array don't know about the parent structure.
		if ( $this->get_parent_property() instanceof Papi_Property_Repeater ) {
			$this->cache = false;
		}

		$value = parent::format_value( $value, $slug, $post_id );

		return array_shift( $value );
	}
public function format_value( $value, $slug, $post_id ) {
		if ( ! is_array( $value ) ) {
			return [];
		}

		// Fixes issue when flexible and repeater are used with group property
		// cache since we use repeaters format value function that cache values.
		// At this point the value array don't know about the parent structure.
		if ( $this->get_parent_property() instanceof Papi_Property_Repeater ) {
			$this->cache = false;
		}

		$value = parent::format_value( $value, $slug, $post_id );

		return array_shift( $value );
	}
Format the value of the property before it's returned
to WordPress admin or the site.

@param  mixed  $value
@param  string $slug
@param  int    $post_id

@return array