JSON change-password request to /ssl/user-manage-passwords failed

Welcome to the ODK forum, @Axlm! We're glad you're here. When you get a chance, please introduce yourself here. I'd also encourage you to add a real picture as your avatar because it helps build community.

The most common cause for this issue is a misconfigured security.properties file. The location of this file may vary depending on the method you choose to deploy aggregate. Did you use the installer or did you compiled Aggregate yourself?

Another factor that we need to take into account is whether your users are accessing Aggregate directly or via some proxy or load balancer. Can you tell us more details about your deployment?