Sorry to hear that you are unable to login to your Virgin Mobile online account. Apologies as well for the delay in getting back to you. I'm glad to hear that your app is working, this way we know that your login details are working correctly.
Total shambles. Went to your link and asked for login which was confirmed as my primary Virgin email address. Tried to change my password, but perhaps fat fingers, or not knowing your password reuse rules failed. Went to iPad and was told the address had expired 24 hours ago, presumably because your programmers did not program a message for too many attempts on another device. Still waiting for another email to iPad.