We haven't received any similar concerns about this specific function. This may be caused by outdated data in the browser. This happens over time when the stored data will become outdated. Let's perform the browser troubleshooting method to fix this.
First, you'll have to use an incognito browser when logging in to your QuickBooks company. This is done to verify if this is a data-related issue. Then, try to check if you'll be able to send a message to your QuickBooks Bookkeeper. If you're able to do that, you can go back to your regular browser and clear the cache. If not, you can use another supported browser.
Here are the keyboard shortcuts to access an incognito browser:
Microsoft Edge & Mozilla Firefox: Ctrl + Shift + P