Translation in the Display Name is not working?

Summary:

In the system 2 languages have been defined, English and Thai. The names are also in 2 languages. When we set the preference to English the display name and all other places where names are found (person management, employment info and others) are working fine. However when translated to Thai, the names are in Thai, however the title remains in English. In the manage common lookups meaning is defined in English and Thai translation is also defined. What can be the issue and how to resolve it

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