FormatException: Unexpected character (at character 1) <!DOCTYPE html> ^ code example
Example: unhandled exception: formatexception: unexpected character (at character 1)
Finally i resolve the problem using laravel, returning the data in this way
return response()->json($yourData, 200, ['Content-Type' => 'application/json;charset=UTF-8', 'Charset' => 'utf-8'],
JSON_UNESCAPED_UNICODE
I have noticed that this error occurs only in emulator, but not in a physical device.