If you have problems logging into your account - this normally means that you've entered either a wrong username/ e-mail address or a password.
First, check the username. If it is correct please do the following to reset your password: go to Log In > Forgot Password page and enter the e-mail address that you used to Sign up to Quantum.uk. You will receive a link to change your password.
Note! In case you want to change your password please go to Log In/Profile/Account /Security/Change Password page.