Very Poor Interface

Terrible app. I was charged for a months service but I am unable to sign-in to use the service. When I try to sign-in with my email address, I get the message, "enter a valid email address". Then when I try to re-register my email, I get the message, "email already registered". I have been charged through iTunes but do not have access to the services.

Rangerx9 about iFax - Send & Receive Faxes, v4.99.38