Thanks to visit codestin.com
Credit goes to docs.wpcodebox.com

WPCodeBox UI won't load

What to do in case the WPCodeBox UI doesn't load

Clear your local storage

It can happen sometimes that a bad snippet ID is stored in your local storage. Clearing your local storage should fix this. How to clear your local storage (opens in a new tab)

Run a plugin conflict check

In rare cases, some plugins might interfere with the WPCodeBox UI. If your UI doesn't load, try running a plugin conflict check, by disabling all your plugins except WPCodeBox. If the UI loads, you can enable your plugins one by one to find the culprit.