How to FIX Netsuite Error while Removing Parent Company from Sub Customer Record?

Error Message: When you try to change Parent Company then error message comes : “A customer record with this ID already exists.

You must enter a unique customer ID for each record you create.

To correct this record, click back and enter a new customer ID in

the Customer”.

Solution:

There are 2 ways:

When you remove the Parent Company of Sub-Customer Record,
change the name of record and enter unique name.
Enable Allow Override on the Customer record.

1. Go to Setup > Company > Auto-Generated Numbers.

2. Enable Allow Override for Customer.

3. Save.

4. Go to the Customer record

5. Remove the Parent Company

6. Click on save button