When running into this issue, you will need to speak with the Admin for your merchant company.
This issue stems from a User's password expiring, and their User Role not having access to the 'Change Password' page.
How to resolve:
1. You NEED to be an admin within the gateway to perform these actions. If you are not an admin, you'll need to work with your admin, or a Gateway Representative.
2. Login to the gateway.
3. Click on the 'Security' menu on the left, and select 'Roles'
4. Find the role you need to modify, and click on 'Edit' on the right hand side.
5. Then you'll need to Allow Security->Change Password.
6. Save the role changes.
7. You may need to perform a password reset on the user after this.
Unless you have a very specific reason to prevent your users from changing their passwords, we recommend keeping this option enabled for all Roles. As passwords are set to expire after 60 days, and there is no way to change this.