@arktiknova  

Hi, thanks for posting the question on our community. 

To change the TP-Link ID bound to your TP-Link Router, you need to unbind the router from the previous TP-Link ID and then bind it to a new TP-Link ID. There are two methods to do this:

Method 1: Using the Tether App

    1) Login to the Tether App with the previous TP-Link ID. Go to "More" and select "Manager."

    2) Tap the three dots on the right side of your TP-Link ID, then tap "Unbind" to remove the router from the previous TP-Link ID.

    3) After unbinding, log out of your account from the Tether App, and then Log in with your new email. If it's not a TP-Link ID yet, sign up with the new email.

    4) Bind the router to your new TP-Link ID.

Method 2: Using the Web Interface

    1) Login to the web interface of the router using the previous TP-Link ID.

    2) Navigate to the "Advanced" menu and select "TP-Link ID" page.

    3) Unbind the router from the previous TP-Link ID on the same page.

    4) After unbinding, you can bind the router to your new TP-Link ID on the same page.

However, if you don't know which TP-Link ID the router was previously bound to and are unable to log in with the previous TP-Link ID to unbind it, please follow these steps:

    1) Connect the router to the internet.

    2) Reset the router to factory defaults by holding the reset button until the power LED starts flashing.

    3) Set up the router again and bind it to your TP-Link ID.

  @gnz 

Hi, it is fine. If you used to use a TP-Link account to log into Tether app, now it should be OK that you can log into Deco app directly using the same TP-Link account.

  @gnz 

Hi, you may refer to this FAQ to change TP-Link ID, but not all Deco models support it: How to change the owner account on Deco APP

As for deleting TP-Link ID, it is suggested to read the FAQ carefully and operate on your end: How can I delete my TP-Link cloud account?