Once the source account sends the customization to a target account, it cannot receive any Copy Customization requests until the target account's admin approves or rejects the current request. This is in place to ensure that there are no changes in the source account when the process is initiated by the target account.
Once the source account's admin receives the copy customization key from the admin of the target account, do the following:
- In the source CRM account, click Setup
in the top-right corner of the CRM UI.
- Under Data Administration, click Copy Customization.
- Click Send Customization.

- Enter the key and click Send Copy Customization.

- Click Yes, Proceed.
- An email will be sent to the admin of the target account to notify them of the sent customization.