Shopify is using cookies for the app login functionality. If you are unable to login to Judge.me Product Reviews, please try the following steps:
A login mix-up can happen if different stores have active sessions within the same browser. At that point, changes you make may be done in the other store. This is because if you switch Shopify admins while doing work, the shop identifier we receives changes so the settings we think you're updating also changes.
To solve this issue: Use different browsers or incognito/private window when you work on two different stores. Or make sure you are not logged in at two stores at the same time.
We encountered issues were Judge.me app users with staff account were not able to login. Only account owners and staff accounts with
full permissions were able to login.
Troubleshooting: Provide staff accounts with full access, then reverting their access back to limited immediately. This will toggle your staff member's account and will provide them with access to the app again. (Tip from Shopify)
Oauth error invalid_request :
Oops, something went wrong What happend? Oauth error invalid_request : This app is requesting to be reinstalled and your account does not have permission to grant the requested access. You may be able to resolve this issue by reinstalling the app as the account owner.
To solve this issue: We increased the required permissions on 14 June 2018. The new permission have to accepted by someone with a full staff account (or an account which covers all needed permissions new + old). Until then, nobody with a limited account will be able to login into the app from Shopify. This is part of Shopify security.
Please login, and accept the change in permissions, with your account and then everyone else in the team should be able to login as well. They may require a logout + login from their Shopify accounts to reset the session.