I am 100% sure my replies “went through”, only to discover they no longer existed the next day.
One example is in the chat. I replied to @user000, but then had to do it all over again, since my messages were gone.
Another example is this thread. The post you see is what I had to type out from memory (again), since the original post was vanished.
I believe there was another post, but ironically, I cannot retrieve it since it’s gone. It’s no longer in my notifications either.
It seriously is like a chunk of time went missing.