Access to supplier portal when a parent supplier is created for a existing parent supplier.

Summary:

We have a requirement where we create a parent supplier(Assume ABC) for a existing parent supplier(Assume XYZ). XYZ has created a user portal with an email id xyz@gmail.com.

However the new parent of XYZ ie ABC was created and xyz@gmail.com need access to ABCs Supplier Portal. We tried to remove the id and add it to ABC Supplier but system throwed an error(even after deleting the account from security console)

Can someone please help us on the same where contact from XYZ can get access to ABCs supplier portal?

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