If you've attempted to go to a website and been shown a page that says that the site was blocked or might be malicious, that means that your organization's policy has blocked that site. These policies can apply to large categories of sites so it's possible that the site was inadvertently caught - what we call a "false positive".
If you believe that the site you were trying to connect to is safe, you should contact your organization's IT administrator or help desk and ask them to update their policy to allow this site.
If you are using Outlook, you might be able to configure some of the premium security settings. See: Advanced Outlook.com security for Microsoft 365 subscribers.
