Get wrong result after converting byte array to String and back in Java

I got a chain of workers that work with byte array, but they have to receive and translate String and char array to the work method work(@NotNull Object data, @NotNull Object prev) as well. So I convert byte array in one worker to String nextWorker.work(new String(result, "UTF-16BE"),this); and translate it to another worker in work method where it converts back to byte array if(data instanceof String){workingData = ((String)data).getBytes("UTF-16BE");}, but result is wrong in some cases ( i pass byte arr size of N and get after byte arr size of N - 2 or something like that, and missed bytes are not from the begining or ending of that array). Can anybody help me to solve this problem or give advise why it happens.