Hi Hevin,
When you create the service for Guest using Service Template/Wizard, In "Access Restrictions" tab, you can set the "Maximum number of devices allowed per user" to 1.
This will restrict the each guest user account to 1 device.

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Kapildev Erampu
PreSales Consultant
Aruba, a Hewlett Packard Enterprise company
Sydney, Australia.
Any opinions expressed here are solely my own and not necessarily that of HPE
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