Just yesterday, I've continue writing on an email I've saved in draft earlier.
After finishing up the email contents and I sent the email to the recipient.

What happens was, I checked my sent box and open up the email message I've sent out, to my horror, the contents was only what was there when I've saved to draft earlier and not including the rest which I've added on it.

Please advise what had went wrong?
Felt so depressed with the lost portion of the email message which I've spend hours working on it.

~Ng Bee Ling