in version 12 enterprise:

* Activate developer mode, and switch to super user.

* Find odoobot in user accounts by filtering for inactive users.

* You will see a "related partner" field. Click on this field and open the related partner.

* Change email address from odoobot@example.com to reflect your own email domain name.

FYI

Log into your system as the admin account but click "log in as SuperUser". This will give you access to the Odoobot user account. 

Within the user menu, you can find the Odoobot user by changing the user filter from internal to inactive.

From this location, you can change the Odoobot username or email address.

I tried this option but didn't work.please suggest another solution.

Hi,

You can set the Odoo Bot Status to disabled from the Preference, 

Thanks