Hi Sanjay,
Based on the the resource center article How do we downgrade our service, I would recommend contacting your CSM who can guide you through this.
I believe that when you downgrade the permissions for the higher licenses will be removed, but if you have already used the license, you will still be billed for the it for the current billing period.
There is also some advice on this community post
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Sam Jillard
Online Community Manager/Moderator
Genesys - Employees
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