"siteurl" and "home" Automatically Changing

We’re moving our WordPress site to a new domain.

We update “siteurl” and “home” in mysql.

UPDATE wp_options SET option_value = replace(option_value, 'http://www.olddomain.com', 'http://www.newdomain.com') WHERE option_name = 'home' OR option_name = 'siteurl';

Then when logging into wp-admin, those fields get automatically changed back to the old domain. We check the data in mysql and those fields are automatically changed back.

The only way to get logged into the site with the new domain is to remove modify privileges from the mysql user that WordPress uses. Then it’s unable to make the change since it doesn’t have privileges.

We completely removed all files from the plugins directory.

Does anyone have any idea how this is happening?