Yahoo mail verification ??

Hi,

I had to change my Yahoo mail password today.

I've tried to update the account on the Mail app on my iPhone.

I enter the password and a window appears asking me to login to my yahoo account to verify my ID.

I click Continue and Safari opens a Yahoo page.

I login successfully but when I select Done in the Mail app setting the account asks me to verify again.

Any ideas what is wrong?

Regards