Please note: if your 1:1 is synced with a Google Calendar, you must change the time of your 1:1 in Google, which will then update the time in Lattice!
As a direct report, you can change the time of your next 1:1. To do so, start by click "Plan next 1:1" at the top of your "You" page.
When in your 1:1 click "Change time" on the top right:
Select the new time for your 1:1 and hit "Save Time" in the top right corner.