AirBnB Website not user friendly

It appears that it is impossible to change my email address on AirBnB. I signed up 5 years ago and haven't logged in since. To sign in or book you have to get a code via sms. Fine. But the next step is to get another security code via emai. There is no option to change an email address. When I typed in at the "How can we help?" I asked: How can I change my email address. The answer: We will send you an email!!!!! Really? How?