To set up an omnichannel for customer service, navigate to the power platform admin center. Choose the environment.
In the left pane, expand Resources and select Dynamics 365 apps.
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On the Dynamics 365 apps page, select the ellipsis for More application actions next to Omnichannel for Customer Service, then select Manage.
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Select OK.
Select the Consent on behalf of your organization checkbox.
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On the Manage Omnichannel Instances page, select Add Environment to add an environment. Omnichannel is set up for the organization environment that you add here.
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Select the environment from the dropdown list and follow the instructions to enable multiple channels.
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Chat: To enable chat, set Add chat? to yes and click next.
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Enable Voice
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Enable SMS
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Add Social
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Add Microsoft Teams
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On the Confirmation page, verify your selections, and then select Finish to provision Omnichannel for Customer Service in your organization.
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The setup can take several hours (2-3 hours).
After the setup is complete, the selected channels will be enabled in the environment.
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Provide the Omnichannel access roles to the user.
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Turn on Apps in Power apps
Omnichannel apps are installed but it is not turned on by default. It has to be turned on.
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Read: How to create an access team in D365?