How to Restrict Slack Logins
If your company uses Slack, you can choose to restrict this type of login as shown below.
Step 1. Team integrations
Go to your account and click your team's name on the top left corner to access the dropdown menu. Click Team integrations. Make sure your Slack Workspace is connected.

Step 2. Uncheck Slack
Once you're there, click Admin settings and then uncheck the Slack permission.

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