Durango Hi. Welcome.
We’re all getting the error messages from time to time, although it has gotten better.
If you get the error message, just hit the “X” in the red box, then refresh. Then it’ll post. If it says ‘unknown’ where the party you’re tagging should be, you can edit it (three dots in the lower right corner) and put the name in.
I’m sure it’ll get fixed soon enough. That’s for a desktop or laptop.