Just finished act 5, strange reward in my stash titled “Message”

Autisticzar

I’ve had MCOC for a while now, and just recently, I’ve been playing more and finished act 5 a few days ago. Soon after, a reward appeared in my stash called “Message” and contained a bunch of tier 5 and tier 4 catalyst fragments. I have tried pressing the claim button, and I closed and reopened my game multiple times. I might just be dumb, but I do not understand what is happening. Please help!