I signed up for an Adobe CC free trial with a new account. When I manage that account, it says under Plans and Products, "You have access to 30-day free trials of all our products, limited access to services, and 2 GB of cloud storage." Despite signing up, when I try and sign in through the CC desktop app, I get a notice that says, "We couldn't find a Adobe Photoshop CC subscription associated with this account." So, I'm unable to use my free trial.
If we understand you correctly, you are using a trial version and you are getting this message "We couldn't find a Adobe Photoshop CC subscription associated with this account" in Creative Cloud app.
We would like to know if you have installed Photpshop CC on your machine or not? Kindly share the screenshot if there is any other message that you are getting.
Meanwhile, here is the information around Adobe trial software expired early