Issue after adding to the cart with custom input field in woocommerce

I have an issue trying to ad this code in child functions.php to get the text input field in a single product page and this error was returned after adding to the cart:

WARNING: CALL_USER_FUNC_ARRAY() EXPECTS PARAMETER 1 TO BE A VALID CALLBACK, FUNCTION ‘ NJENGAH_PRODUCT_ADD_ON_VALIDATION’ NOT FOUND OR INVALID FUNCTION NAME IN /USERS/LUISRODRIGUES/LOCAL SITES/QSH/APP/PUBLIC/WP-INCLUDES/CLASS-WP-HOOK.PHP ON LINE 289

Code added in functions.php to get tex input fields in single products page:

/**

* @snippet Add an input field to products – WooCommerce

*/

// —————————————–

// 1. Show custom input field above Add to Cart

add_action( ‘woocommerce_before_add_to_cart_button’, ‘njengah_product_add_on’, 9 );

function njengah_product_add_on() {

$terms = [‘desenhos’];
if ( has_term( $terms, ‘product_cat’, get_the_ID() ) ) {

$value = isset( $_POST[‘custom_text_add_on’] ) ? sanitize_text_field( $_POST[‘_custom_text_add_on’] ) : ”;

echo ‘<div><label>Custom Text Add-On <abbr class=”required” title=”required”>*</abbr></label><p><input name=”custom_text_add_on” value=”‘ . $value . ‘”></p></div>’;

}
}

// —————————————–

// 2. Throw error if custom input field empty

add_filter( ‘woocommerce_add_to_cart_validation’, ‘ njengah_product_add_on_validation’, 10, 3 );

function njengah_product_add_on_validation( $passed, $product_id, $qty ){

if( isset( $_POST[‘custom_text_add_on’] ) && sanitize_text_field( $_POST[‘custom_text_add_on’] ) == ” ) {

wc_add_notice( ‘Custom Text Add-On is a required field’, ‘error’ );

$passed = false;

}

return $passed;

}

// —————————————–

// 3. Save custom input field value into cart item data

add_filter( ‘woocommerce_add_cart_item_data’, ‘ njengah_product_add_on_cart_item_data’, 10, 2 );

function njengah_product_add_on_cart_item_data( $cart_item, $product_id ){

if( isset( $_POST[‘custom_text_add_on’] ) ) {

$cart_item[‘custom_text_add_on’] = sanitize_text_field( $_POST[‘custom_text_add_on’] );

}

return $cart_item;

}

// —————————————–

// 4. Display custom input field value @ Cart

add_filter( ‘woocommerce_get_item_data’, ‘ njengah_product_add_on_display_cart’, 10, 2 );

function njengah_product_add_on_display_cart( $data, $cart_item ) {

if ( isset( $cart_item[‘custom_text_add_on’] ) ){

$data[] = array(

‘name’ => ‘Custom Text Add-On’,

‘value’ => sanitize_text_field( $cart_item[‘custom_text_add_on’] )

);

}

return $data;

}

// —————————————–

// 5. Save custom input field value into order item meta

add_action( ‘woocommerce_add_order_item_meta’, ‘ njengah_product_add_on_order_item_meta’, 10, 2 );

function njengah_product_add_on_order_item_meta( $item_id, $values ) {

if ( ! empty( $values[‘custom_text_add_on’] ) ) {

wc_add_order_item_meta( $item_id, ‘Custom Text Add-On’, $values[‘custom_text_add_on’], true );

}

}

// —————————————–

// 6. Display custom input field value into order table

add_filter( ‘woocommerce_order_item_product’, ‘ njengah_product_add_on_display_order’, 10, 2 );

function njengah_product_add_on_display_order( $cart_item, $order_item ){

if( isset( $order_item[‘custom_text_add_on’] ) ){

$cart_item[‘custom_text_add_on’] = $order_item[‘custom_text_add_on’];

}

return $cart_item;

}

// —————————————–

// 7. Display custom input field value into order emails

add_filter( ‘woocommerce_email_order_meta_fields’, ‘ njengah_product_add_on_display_emails’ );

function njengah_product_add_on_display_emails( $fields ) {

$fields[‘custom_text_add_on’] = ‘Custom Text Add-On’;

return $fields;

}

add_filter( ‘something’, ‘regis_options’ );`

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