Error 0 - Undefined constant "Y"

Hello, 

I got the below error message once trying to add a module position to the template. The site is running with Joomla 4.3.3, PHP 8.1.20. Any idea how to solve it? I have tried to restore the previous backup and still have the same error message on the front-end. The back-end is working fine.

Thank youUndefined constant "Y"
/home/xxxx/public_html/templates/corporate2/index.php:286Call stack#FunctionLocation1()JROOT/templates/corporate2/index.php:2862require()JROOT/libraries/src/Document/HtmlDocument.php:7413Joomla\CMS\Document\HtmlDocument->_loadTemplate()JROOT/libraries/src/Document/HtmlDocument.php:7964Joomla\CMS\Document\HtmlDocument->_fetchTemplate()JROOT/libraries/src/Document/HtmlDocument.php:6135Joomla\CMS\Document\HtmlDocument->parse()JROOT/libraries/src/Application/CMSApplication.php:10126Joomla\CMS\Application\CMSApplication->render()JROOT/libraries/src/Application/SiteApplication.php:7247Joomla\CMS\Application\SiteApplication->render()JROOT/libraries/src/Application/CMSApplication.php:2988Joomla\CMS\Application\CMSApplication->execute()JROOT/includes/app.php:619require_once()JROOT/index.php:32

Hi
what is the code that you have Line 286 in the file templates/corporate2/index.php ?
CEd

Thank you for your reply.
I have this code: </br> ©<?php echo date(Y); ?>
There is a class undefined too above: 
<section id="row3"  class="tck-row">
        <div class="inner">
            <div class="flexiblecolumn valign-center" id="row3column1">
    <div id="custom1" class="undefined">
        <div class="inner">

ok then check in your template you must have a custom code block in this area, update the code with (add quotes to the Y)

Okay! The home page is working now. However, I have a white page with the following message: [an error occurred while processing this directive] on all the other pages.

go in your admin >> config >> system >> debug >> set it to YES
then tell me if the message is more relevant