With Atlassian Sales
1- To request a quote, one can submit a ticket through the Billing form online. The quote will then be delivered via email within one business day to the individual listed as the billing/technical contact.
2- Additionally, Atlassian offers the option to request a quote by phone. Customers can use one of the following numbers based on their location and time zone: +1 512-640-3000 Option 1 (Austin, TX), +31 20 796 0060 (Amsterdam, Netherlands), or +61 2 9262 1443 (Sydney, Australia). Note that while Atlassian does not have a toll-free number, they encourage customers to use the most convenient phone number provided above.
Buy a license yourself
Go to the Atlassian Marketplace and search for "Calendar for Jira" app.
Choose the appropriate version of the app based on the Jira version you are using.
Select the desired pricing plan that best fits your needs.
Click on the "Buy now" button to proceed with the purchase.
If you have not logged in to your Atlassian account, you will be prompted to do so. If you do not have an account, you can create one for free.
Complete the billing information and review the order summary.
Click "Submit order" to complete the purchase.
After the purchase is complete, you will receive a license key that can be used to activate the Calendar for Jira app in your instance of Jira.