I am using Ignition V8.1. After login the gateway, When I click to configure page showing “You do not have permission to access this page. Please refer to your Gateway administrator”. I couldn’t reset my trial period.
This issue arises, after I changed the security page in gateway. I couldn’t reset password using gwcmd. 
:(. Can you please let me know, how to resolve the issue.
it stlil shows the login button, you sure you logged in correctly?
Usually a gwcmd password reset and a gateway restart solves the problem. This forces you to go through commissioning again after the Gateway restarts, but only for the step where you define a new administrator username and password, which should get you into the Gateway Web Interface status and config pages.
If you tried this, and it doesn't work, and you continue to run into the access denied page, consider reaching out to support so that they can take a closer look.
I exported my project backup and reinstall my Ignition designer then the problem got cleared.
Thank you guys.