Your community timezone is automatically set to GMT+00 when you first create your community.
This setting determines the default timezone used when scheduling events, posts, and automated messages inside your community
Step 1: Click Admin Panel.

Step 2: On the side menu, click Settings & Data and select Settings.

Step 3: Scroll to the section titled Timezone and Currency.

Step 4: Select your community timezone from the dropdown menu and click Save Settings once you are done.

Note
New events will be created in your selected timezone.
Scheduled posts and emails will be released in your configured timezone as well.
When members are viewing event times and dates, they will be automatically converted to their local timezone for convenience.