Personal and Developer Plans
These plans include unlimited licenses. You can simply remove the account you do not need to be synced and add the account/s you want to sync.
Company plan
Go to your dashboard to assign or re-assign the Company plan to your preferred account.
Click on the Company tab
Remove the currently assigned account to your license
Assign the new account you want to use your license with. You will get a pop-up window to confirm this action. Note that you will not lose access to the dashboard -- you are simply removing the license from the account.

If you bought the plan for the wrong owner account, please reach out to support@insynchq.com and include your invoice.