Please read the following post:
https://community.zammad.org/t/asking-for-help-on-community/2262
- Update all needed information (installation type and stuff)
- Provide log files (/var/log/zammad/production.log)
- Additionally provide hardware information and the number of agents you do have
While you’re at collecting informaiton, please also run the developer console in a browser where this happens and check if there’s any console messages