Hi @Katrina Gaskill ,
Do you mean deleted user is still a team member of a specific team? If so, you should sign out and re-sign in the mobile client to check if it’s synced. Also you could uninstall the mobile client and re-instill to clean caches and see if it’s synchronized with Office 365.
Based on my tests and experience, after you deleting users in M365 Admin Center, the access to M365 should be lost immediately, so you don’t have to worry it.
The data of the deleted user could be kept for 30 days and you could restore during this period, so we could still search this user and see his information before he is permanently deleted. Check this doc for more: Delete a user from your organization
Best regards,
Lou
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