Verify if you signed up with Google (SSO).
Verify whether your account was created directly via your email address, or through Google (SSO). It's possible you may have two separate PSE accounts – one for prosoundeffects.com and another for SoundQ, so make sure you're using the account (and method) you used to register SoundQ. We're working on a way to merge these to avoid confusion.
If that doesn't work, or you're receiving a "bad gateway" message, please submit a support ticket.