Chinese names on official documents, and why yours may not match
One set of characters, three different spellings, three documents that no longer obviously belong to the same person. This is the single most common problem in certified translation in this region, and it is not a translation error.
Why the spellings differ
A Chinese name is written in characters. Roman letters are an approximation of how those characters sound, and which approximation you get depends on who was writing and when.
Hanyu Pinyin renders 陈 as Chen. Cantonese gives Chan, Hokkien gives Tan, Teochew gives Tang or Chin, Hakka gives Chin. None of these is wrong. They are different systems, applied at different times by different registrars, to the same character.
In Singapore and Malaysia this is compounded by history: dialect spellings were the norm for generations, then Pinyin became standard for mainland documents, and many families now hold both.
Where it causes trouble
A mainland birth certificate says Chen Meiling in Pinyin. A Singapore identity card says Tan Mei Ling, the dialect spelling recorded when the family registered here. A degree certificate from Taiwan uses Wade-Giles and says Chen Mei-ling.
Translate each one literally and you have produced three documents naming three people. The officer reading them has no way to know they are the same person, and the safe decision for them is to refuse the set.
Which spelling wins
The passport. Not because it is more correct, but because it is the document every other one is checked against, and the one whose spelling follows the applicant through every future application.
A translation should carry the passport spelling and note the original where the two differ, rather than choosing one and hiding the other. That way the reader can see why the documents disagree, which is precisely the question they were about to ask.
Say so when you send the documents
If you know your name appears differently across your papers, say so at the point of asking for a quote and give the passport spelling. It takes a sentence and it prevents the most expensive kind of rework, the kind discovered after submission.
The same applies to a name that changed on marriage, a name with a generational character some documents omit, and a name where the family and given order was reversed by a clerk somewhere along the way.