Hi Jennifer,
Hope you are well!
I got your account checked and it seems that you have subscribed to the 'Pro - Plan' for Event Diagramming. In this plan you can only have 5 Floorplans and deleting them is not an option.
I hope this helps. Please let us know if you have any further questions.
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Raashi Semwal Khati
Senior Quality Analyst
Cvent
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