Moved host, blogs now redirect

Hi, i recently moved hosts and now using Plesk CP. I managed to move all my WP files and databases over ok but the blogs redirect to https://mydomain.com and refuse to accept https://www.mydomain.com

what ive done so far is navigate to ‘settings > general’ and change the “WordPress Address (URL)” and “Site Address (URL)” to include the www.

this then kicks me out of the admin panel and sends me to:
https://mydomain.com/wp-login.php?redirect_to=http%3A%2F%2Fmydomain.com%2Fwp-admin%2Foptions-general.php%3Fsettings-updated%3Dtrue&reauth=1

which refuses to accept my admin login details and sends me to https://mydomain.com/wp-login.php and every attempt fails, any attempt to login at https://mydomain.com/wp-admin/ redirects to https://mydomain.com/wp-login.php

I then logged in to phpmyadmin and navigate to “wp_options” changed the “siteurl” back to https://mydomain.com and everything works ok again, but still wont let me use the www.

Any idea’s what im doing wrong, my host has only asked me to do what ive done already, and im all out of ideas

Thanks