The following reasons may cause Json verification to fail.
Error reasons that make it difficult for you to find out the truth:
1. The non-numeric key values in the Json string do not have double quotes.
2. There is a tab character like \t in Json, which looks the same as a space, but because of its existence, the verification fails, so just remove it.
3. If the editor has Bom header, it will also cause Json verification to fail.