I am 80 years old, and found a mistake because I helped Angela set up "angelascurti213@gmal.com", mine is "wschneider842@gmail.com.

I am 80 years old and don't access profile or anything "complicated" very often. Yesterday night I somehow got into some page showing information on my account. At the top it showed my daughter-in -laws email address "angelascurti213@gmal.com". My email address is "wschneider842@gmail.com". Back in April she was visiting us and I helped her set up an email address with Firefox. I have no idea how her email address in essence usurped my Firefox information. I intended to correct the mistake however, I don't know her passwort. To change anything you are sending emails to her email address. She doesn't live close by, she is at work now, so I can't connect with her. how do I change my Firefox account, which I have had for many years with the correct information?