Problem
WebSpellChecker is ignoring words in all capitalizations like “CONFICENCE” and doesn't proceed mistakes in them.
Solution
To avoid the problem add the ignore_all_caps=0 parameter to your Web API request, which regulates whether to ignore capitalized words or not. The value 0: Do not ignore all words written in capital letters.
We plan to release the fix for the issue until the end of March 2019.