When I copied and pasted the UUID, letters were capitalized and dashes were already included. I used both immediate and near proximity. For immediate, I had to be right on top of the beacon. For near, the conversation was triggered when I was about 15 feet away (give or take).
What helped me troubleshoot this was discovering the brand of the beacon I was using. Once I found the brand, I was able to learn that I needed the app. From what I could tell when I was searching the Internet for an answer, the beacons should come with a preset UUID? Maybe try calling customer service for the brand? They might have an app or something that could help configure the beacons.
Here is what my UUID looks like: 3Y237754-CB6D-4A0F-ADF2-F4800BA9JJA6 - I had the option to change it in the app, but I didn't.
I'm not sure how to confirm Bluetooth LE... I know these were recently ordered?