You can access your account from another computer, but you must be certain that NO ONE else using that computer has a Fusion Cash account.
If there is another account associated with that computer, then you both will be banned.
That is why it is recommended that you NOT use a public computer (library, hotel, work etc) to access your account. You just don't know who else might use that computer to access their FC account.
Don't know enough about using a mobile phone to access the web. Would depend on whether the connection is unique to you -- ask support and provide your connection information if you can.