After installing SuiteCRM, I was unable to receive emails

After installing SuiteCRM, I was unable to receive emails.
After troubleshooting, the issue was traced back to the ID command.

Upon confirming the use of php-imap2, the relevant code was found in:

vendor/javanile/php-imap2/src/Roundcube/ImapClient.php:1786

/**
 * Executes ID command (RFC2971)
 *
 * @param array $items Client identification information key/value hash
 *
 * @return array|false Server identification information key/value hash, False on error
 * @since 0.6
 */
public function id($items = array())
{
    if (is_array($items) && !empty($items)) {
        foreach ($items as $key => $value) {
            $args[] = $this->escape($key, true);
            $args[] = $this->escape($value, true);
        }
    }

    list($code, $response) = $this->execute('ID',
        array(!empty($args) ? '(' . implode(' ', (array) $args) . ')' : $this->escape(null)),
        0, '/^\* ID /i');

    if ($code == self::ERROR_OK && $response) {
        $response = substr($response, 5); // remove prefix "* ID "
        $items    = $this->tokenizeResponse($response, 1);
        $result   = array();

        if (is_array($items)) {
            for ($i=0, $len=count($items); $i<$len; $i += 2) {
                $result[$items[$i]] = $items[$i+1];
            }
        }

        return $result;
    }

    return false;
}

vendor/javanile/php-imap2/src/Roundcube/ImapClient.php:943

// Send ID info
if (!empty($this->prefs['ident']) && $this->getCapability('ID')) {
    $this->data['ID'] = $this->id($this->prefs['ident']);
}

$auth_method  = $this->prefs['auth_type'];

Final Solution

Modified the connection parameters in:
vendor/javanile/php-imap2/src/Connection.php:126

$success = $client->connect($this->host, $this->user, $this->password, [
    'port' => $this->port,
    'ssl_mode' => $this->sslMode,
    'auth_type' => $this->flags & OP_XOAUTH2 ? 'XOAUTH2' : 'CHECK',
    'timeout' => -1,
    'force_caps' => false,
    // Add ID Command parameters
    'ident' => [
        'name' => 'SuiteCRM',
        'version' => '8.8.0',
        'vendor' => 'SugarCRM',
        'support-email' => 'xxx@163.com',
    ]
]);

By adding the ID command parameters (ident), the email reception issue was resolved.