I have managed to address the "private messages" bug. The problem was originally that people were not able to reply to private messages that they had received. It should now be resolved!
Feel free to try this out, if you are still having issues with this feature feel free to leave a comment below and I will read through them. I am still busy working through the bugs list from the last article and will update you with my progress as I get through them!
Thanks for your continued help everyone!