TypeError: strtotime() expects parameter 1 to be string, null given in /vendor/magento/module-security/Model/AdminSessionInfo.php:136

AdminSessionInfo.php

    #/home/production/vendor/magento/module-security/Model/AdminSessionInfo.php:136
    public function isSessionExpired()
    {
        $lifetime = $this->securityConfig->getAdminSessionLifetime();
        $currentTime = $this->dateTime->gmtTimestamp();
        $lastUpdatedTime = $this->getUpdatedAt();
        if (empty($lastUpdatedTime)) {
            return true;
        }
        if (!is_numeric($lastUpdatedTime)) {
            $lastUpdatedTime = strtotime($lastUpdatedTime);
        }

        return $lastUpdatedTime <= ($currentTime - $lifetime) ? true : false;
    }