The UTC setting is "under the hood" for some calendaring platforms. They then add a bit of a veil over that and show you everything in your timezone. But in some cases, they show us UTC, which will not be correct for your timezone.
The best way to handle it on your booking page is to override the timezone setting. Under Times & availability Language & timezones, Uncheck the box next to "Automatically detect timezone from my calendar" and then choose your timezone from the dropdown.
Here's an help article from Fruux on adjusting your calendar timezone.
Within Microsoft calendars you may also be able to manually override your timezone reading. See more here: Getting the timezone setting right for your booking page