GST Log In Issue...

If you are logging in the first time, please use this link to login: https://services.gst.gov.in/services/newlogin

If you have already logged in before, then you might want to recheck your username. Ordinarily, one might get confused and enter GSTIN in the username field, which is wrong. If you're doing this right and there is something else that's wrong, you can head to your old VAT office (LVO) or Service Tax Department and consult with them, they might be in a position to help you out.

Good luck.