Configure "Advanced Settings" of your Admission Item and include the Sessions you are allowing them to choose or providing with Admission.
Select the sessions in "Session Association" and these will be included when they choose the Admission Item. -OR -
Set "Rules for Optional Sessions" to allow attendees to only select a particular number (or as many sessions as they want), of the session you make available to them to select. They will be charged an additional fee for the session if you are charging a fee.
With this setup them can select an Admission Item, and in the Session screen review which sessions are included or available. Then if they want to change their Admission Item, they select Previous and select a different Admission Item which has a different set of sessions included or available.
Hope this helps!
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