Changing status of order falls into a loop

[Valentina R]

When clicking on the order action or changing status in the 'edit order' screen, it goes into a loop - returns server error 500 and when later looking at the Order Notes it gives a long list (100+) of the same action "Appointment #2064 status changed from “Unpaid” to “Paid & Confirmed”

[Željan Topić]

Fixed with 3.0.8