My mom recently just received a text saying that she had changed her email address from ***Hotmail.com to ****outlook.com

I know for a fact she didn't change anything and now we can't log into her email at all. what do I do?!

please help! I tried to sign up for a new email with the same name so she doesn't have to change for her work and other important things but it said that It is a Hotmail so I can't sign up again? something like that...

she have important emails coming in from work, she need this immediately!

thank you