Facebook says I'm talking to myself as opposed to who I actually am talking to?

[The cobras venom]

So Facebook has stuffed up. The question is wrote as if my girlfriend asked it. Anyway, I was on my spam folders an there were 2 messages from my girlfriend in separate conversations for some reason but both were the same which was a tumblr link. I deleted them, and to her, it says I left the conversation when infact we are still talking. To her, it says shes talking to herself on the left sidebar where all the conversations are but within the conversation you can see both our names and messages. I've tried adding myself to the convo on her account but it's not working. Please help, it's fucking annoying!

[Jamerican Steve]

You failed to mention how you are connecting to FB so don't expect any
answers or answers that will be for browsers or devices you are not using.