You will need to contact each one of the clients using Corridor.
Contact Corridor Support if you need the contact information for one or more of your clients.
Unfortunately, Corridor Support is not able to update your Corridor profile until the tax ID is updated in each of your clients' systems. You may copy Corridor Support in your communication with the client. Let us know when all the clients have made the requested changes (screenshots from your client's system showing the update are very helpful).
Corridor Support will proceed with changing the Tax ID in Corridor once all the clients have approved and updated the Tax ID in their systems.