Single Campaign Monitor account for Multiple websites?

I have a Campaign Monitor account and a website liked to it.

I now want to add another website to the same Campaign Monitor account. Can this is done? IF yes, how to I link it?

I tried connecting the existing Campaign Monitor account through my site’s wordpress. After entering CM credentials, on the Allow access to your account? page, on typing the domain to verify and clicking allow access, I get the below error –
We’ve encountered an error
It looks like the page you’re after does not exist. You may have mistyped the URL, or something has gone pear-shaped on our end.