Apple released macOS 10.13 High Sierra on September 25, 2017 and changed the way macOS reports Language & Region preferences to MATLAB. When you update to macOS High Sierra, we recommend you upgrade to MATLAB R2017b, which can bedownloaded here.
If you cannot update MATLAB to R2017b, then please follow the instructions below to see if you are affected and how to resolve the issue.
Determine if the Language your Mac is set to. You can do this by opening the “Language & Region” preference pane in System Preferences. Your current Language is at the top of the list on the left.
Is your default language set to any of the following languages?