Zend certified PHP/Magento developer

magento 2.4 show message when customer logs in from checkout page

I need to show a message after customer logs in. In order to do so, I created a afterAuthenticate() plugin that gets called both when the customer logs in from the login page and when the customer logs from the checkout page.

However, the plugin should show a message to the customer. The message is correctly shown when the customer logs in from the login page but it doesn’t appear when the customer logs in from the checkout page.

I used the MagentoFrameworkMessageManagerInterface::addWarningMessage('my message') . I also tried using the complex message, creating the di and then the phtml with my messsage, but the result is the same: the message shows on all pages but not on checkout page.

How can I add a message on the checkout page?