add_filter( 'gform_validation', function ( $validation_result ) {

	$duplicate_field_ids[63] = [
		[ 21 => 'message', 23 => 'message', 27 =>'message' ],
		[ 21 => 'message', 24 =>'message' ],
		[ 25 => 'message', 26 =>'message' ],
	];

	$duplicate_field_ids[32] = [
		[ 3 => 'message', 17 => 'message', 46 =>'message' ],
		[ 22 => 'message', 17 =>'message' ],
	];

	function get_duplicate_keys(array $array): array {
		$value_counts = [];
		$duplicate_keys = [];

		foreach ($array as $key => $value) {
			if (isset($value_counts[$value])) {
				if ($value_counts[$value]['count'] === 1) {
					// First duplicate occurrence, store previous key
					$duplicate_keys[] = $value_counts[$value]['first_key'];
				}
				// Every duplicate occurrence after the first, store current key
				$duplicate_keys[] = $key;
				$value_counts[$value]['count']++;
			} else {
				$value_counts[$value] = ['count' => 1, 'first_key' => $key];
			}
		}

		return $duplicate_keys;
	}

	if ( ! function_exists( 'check_is_multi_input_field' ) ) {
		function check_is_multi_input_field( string $field_type ): bool {
			return 'name' === $field_type || 'address' === $field_type || 'checkbox' === $field_type;
		}
	}

	function get_values_with_key_pattern(array $array, string $id) {
		$matching_values = [];
		$pattern_regex = '/^input_' . $id . '_\d+$/';

		foreach ($array as $key => $value) {
			if (preg_match($pattern_regex, $key, $matches)) {
				if ( ! empty( $value ) || $value === '0' || $value === 0 || $value === 0.0 ) {
					$matching_values[] = $value;
				}
			}
		}

		return implode(' ', $matching_values);
	}

	$form = rgar( $validation_result, 'form' );
	$form_id = rgar( $form, 'id' );
	$fields = rgar( $form, 'fields' );
	$field_ids = array_column( $fields, 'id' );

	if ( in_array( $form_id, array_keys($duplicate_field_ids), true ) ) {
		foreach ( $duplicate_field_ids[$form_id] as $fields_list ) {
			$values = [];
			foreach ($fields_list as $field_id => $message) {
				$field_type = $fields[array_search( $field_id, $field_ids )]['type'];
				if ( check_is_multi_input_field( $field_type ) ) {
					$values[$field_id] = get_values_with_key_pattern( $_POST, $field_id );
				} elseif ( ! empty( rgpost( 'input_' . $field_id ) ) ){
					$values[$field_id] = rgpost( 'input_' . $field_id );
				}
			}
			$duplicate_keys = get_duplicate_keys( $values );
			if ( ! empty( $duplicate_keys ) ) {
				$validation_result['is_valid'] = false;
				foreach ( $fields_list as $field_id => $message ) {
					if ( in_array( $field_id, $duplicate_keys, true ) ) {
						$fields[array_search( $field_id, $field_ids )]->failed_validation = true;
						$fields[array_search( $field_id, $field_ids )]->validation_message = $message;
					}
				}
			}
		}
		$form['fields'] = $fields;
		$validation_result['form'] = $form;
	}

	return $validation_result;
});