cancel registration emails not sent

I have events booking setup and with emails being sent OK except for the cancellation emails.
Specifically I'm talking about the admin cancelling the registration from the back end either by adjusting the status of the registration to cancelled or selecting the registration then > Actions > Cancel Registrations.
Both methods are changing it to cancelled but no emails sent.
I have another website using Events Booking and it is sending the emails when doing the same thing so its something with this setup.
I cant seem to find anything in the settings to help. I don't think I've modified anything which would effect this, Its been running for many years, I may have forgotten something.
Anyone with any ideas of where I could check 1st, perhaps I've overlooked something ??? 
 

Hello

One thing you should do is making sure the email messages are setup. Go to Events Booking -> Email & Messages, check and make sure the following messages are configured (not empty)

- user_registration_cancel_subject
- user_registration_cancel_message

If there items are not empty, emails should be sent

Regards,

Tuan

Thank you, that fixed it.
I was surprised this stopped the admin emails sending also. 
I'm not sure sure why these were empty but there are several people who have played with this over the years.
Thanks again Tuan - you are the man!

Ah Yes. When these messages are empty, the system will also not sending email to admin. I will check and change it if it is really needed

Regards,

Tuan