In case you don't use Confluence Premium: Team Calendars is only a premium feature since beginning of 2021 (Team Calendars for Confluence | Atlassian). This might be the reason why it's not working correctly.
You can either switch to Confluence Premium or use another calendar plugin from Atlassian Marketplace.
Hi, Jira users! Do you use Jira alongside Microsoft Teams? We want to hear how you’ve used the power of Jira Cloud and Microsoft Teams (via the Jira Cloud for Microsoft Teams app) to achieve a team...
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