Login to your Google Admin: https://admin.google.com
Go to Data migration.
Select the Email option and click Continue.
On the Email Migration screen:
From the Migration source list, select I don’t know/Other IMAP server.
From the Connection protocol list, select IMAP, then choose an option:
Enter the IMAP server name (for example, imap.yourdomain.com).
Enter the IMAP server name and port number in this format: Name: Port.
Enter the email address and password for your role account(use email id from where you want to migrate ).
Tip: For help with this, see Connection information for common webmail providers.
(Optional) If the connection fails, verify that the role account and connection protocol information is correct. Then, click Connect again.
In the Migration start date and Migration options sections, accept the default options or choose to exclude data that doesn’t need to be migrated.
Click Select Users.
Next: Go to Migrate email for a single user or Migrate email for multiple users.
All migration will be completed without fail.