If you receive the error message "No such entity.", "No such entity with" or "No such entity with customerId" in Magento 2, the issue usually occurred when you try to load not existing object via Magento 2 Repository Class.

To debug this issue, please open the file

vendor/magento/framework/Exception/NoSuchEntityException.php

and at the beginning of the __construct method temporary add debug backtrace code:

foreach (debug_backtrace() as $_stack) {
    echo ($_stack["file"] ? $_stack["file"] : '') . ':' .
        ($_stack["line"] ? $_stack["line"] : '') . ' - ' .
        ($_stack["function"] ? $_stack["function"] : '');
}
exit();

example:

public function __construct(Phrase $phrase = null, \Exception $cause = null, $code = 0)
{
    foreach (debug_backtrace() as $_stack) {
        echo ($_stack["file"] ? $_stack["file"] : '') . ':' .
            ($_stack["line"] ? $_stack["line"] : '') . ' - ' .
            ($_stack["function"] ? $_stack["function"] : '');
     }
    exit();

    if ($phrase === null) {
        $phrase = new Phrase('No such entity.');
    }
    parent::__construct($phrase, $cause, $code);
}

save the file and refresh the page.

You will see the debug backtrace that will allow you to define the issue source and you will get an idea how to fix it.

Usually third party Magento 2 extensions lead up to this problem, so you can override their code and add "try-catch" exception.

Don't forget to revert changes in NoSuchEntityException.php file after you're finished.