A Microsoft app for iOS and Android devices that enables authentication with two-factor verification, phone sign-in, and code generation
Since the Hotmail.com brand was retired in 2013, no new @Hotmail.com address has been able to be created since that time.
If that particular address had been originally created and then deleted, it wouldn't be able to be re-created since that ability is blocked for past addresses in order to ensure that someone doesn't try to abuse these for identity theft, so that's another reason it wouldn't be possible to open this account even if it had existed at one time.
These are fixed policies for Microsoft that if you dig around, you'll find documentation for, so though I'm in no way official, I'm just telling you you're barking up a tree that doesn't even exist, let alone have any possible method of resolving within Microsoft itself.
You'll need to find a way to support that email address function with ClickWorker itself rather than Microsoft, though when I did a search for this same issue online, several online posts suggested that a Live.com address was required, which today are all actually Outlook.com instead, so it's possible that you simply misunderstood the instructions or maybe typed in Hotmail.com yourself in error?
Either way, contacting Microsoft for outdated email domains will never work, so you'll either need to resolve this error with ClickWorker or try another workspace support solution that provides support for the platform you're actually trying to use.
Rob