Overview:

Currently, Any user initiating a first time SSO login using an identifier that already exists in the custodian org - causes an auto migration of the account from custodian to the state tenant it can cause erroneous migration to avoid it user's acknowledgment is required.

If the user is found to match an account in the custodian org when the user tries to login via SSO for the first time, the user should be prompted about the existence of the duplicate account and asked whether the account belongs to them.

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Step 5: Users re-enter the password. If the password is correct initiate account migration else create a new account for the user.

UI Screens 

Verify user via email or phone

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user enters OTP

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Click on the below-mentioned link for further flow.

https://projects.invisionapp.com/share/2YT9CGQNASD#/screens/376879374