Standalone Angular IDE instances (which I am assuming you have) were updated to a new platform in which the TypeScript editor has changed. The ID you are referring to is the older ID, and the upgrade process should have taken care of correcting your workspace, but perhaps that did not happen for some reason.
You should simply close all editors and right click your file > open with > TypeScript :: CodeMix. If you find you need to do this for all your TS files, please ensure TypeScript is selected on the Preferences > CodeMix > Languages > Preferred Editors page.
See https://www.genuitec.com/forums/topic/troubleshooting-codemix-2/ for more details.
Note – if you did not have a standalone install of Angular IDE and do not see the CodeMix icon as described in the above link, please let us know, there may be something else wrong.