When creating the microsoft add-in we have to set the client secret which is being used by our apps to provide contextual information in the add-in. This secret is set to expire at max every 24 month...
You can make use of the Azure portal for configure it with a maximum of 2 years expiry. Also, you can use the PowerShell cmdlet to configure the client secret expiry for more than 2 years. For more info refer: https://o365reports.com/2023/07/20/an-overview-of-client-secret-management-in-azure-ad/