Calendar changing times

I have started using iCloud, and have noticed that my calendar event times have changed from what I first put them in as.

Example, hair appointment this week was moved to 3 hours later, and still unsure of the time of another appointment in January as the time has been changed past business hours.

I am really not sure why this is happening, does anyone have any reasons or ideas?

I have just looked at iCloud and the times are all wrong. However on my phone the events I have updated have not changed yet. Very, very confused.