Hello apadilla824,
Thanks for messaging us here. It's vital you're able to use QuickBooks Messenger so you can communicate with your staff members with ease. Rest assured, I'll be happy to assist you with this so you can achieve your QuickBooks goals.
In order for you to use QuickBooks Messenger, it's important to make sure the multi-user mode is enabled. I encourage you to check out this article here that shows you how to enable and use QuickBooks Desktop Messenger. If you're still having issues, I encourage you to troubleshoot this using the QuickBooks Desktop Tool Hub. The QuickBooks Tool Hub is designed to help fix issues and errors in QuickBooks. Check out this article here that shows you how to effectively use the Tool Hub to your advantage.
Give this a try and let me know what happens. I'll be one message away in case you need additional support.