The Sims 2 : The letters disappears when I type in Thai language

I found the problem when I start to name my sim in Thai language, the letter disappears (example: ‘กวาง’ have 4 characters, but when I start to type, it only show ‘    ’ blank space 4 times). No matter how many times I press repair, it doesn't work. Not only me who found the problem, someone have the same problem in The Sims 4 Thailand community too

Please fix it, thank you