Hi YeshiWangChuk,
what you are seeing is a field that has an associated Domain, but some of the actual data values in your table are not valid codes for the Domain. ArcGIS cannot find a Description, so just shows the code value.
It is a bit odd, if you have used any of the techniques described above to copy data from Enterprise Geodatabase to File Geodatabase, the associated domains would have come with it.
Is it possible some other edits have happened after transfer? - or do you see the same behaviour when you look at the class still in the Enterprise Geodatabase (using ArcGIS tools)?