How to change account status and send email to customer (non-repeatedly)

How to change account status and send email to customer (non-repeatedly)

Hi,

I have created a client form. On the form, I have 2 options being "Operational" and "On Hold".

I have created the code that triggers "On Update" an email is sent to the user about the account change, however, I can't figure a way to stop it doing it - as in only once. Each time I update the form it resends.

Do I have to capture the existing status and compare or something similar to only send it once?

Thanks