That's very strange. Have you been able to open an issue with Atlassian Support? The messages are sending but your own client isn't seeing them received...
Usually most users can fix this issue by fully closing the HipChat client and then reopening it. This fix doesn't work for you?
...from the beginning. We have built up a lot of content in HipChat, with it being a core tool in our distributed company model. While it is true that we didn’t need to move to Slack immediately, we felt it...
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