Hi Jessy,
Within your admission item(s) if you go to the Advanced Settings tab > Edit > And check off the sessions that should be included under the Session Association header and also check them off under the Availability section under limit which sessions are available to invitees: Yes and check off the sessions there as well, they will display in the registration process and be included with no option to deselect.
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Julia Plymack
Senior Customer Success Manager
Cvent
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