When I logged on I saw that I had a “Memory of Rrach” req available and when I tried to open it it said “please try again” so I did and then it gave me a “REQ already opened” not sure what to do. It’s disappeared now. 
is it on your open pack page?
Nope, it’s gone. Not sure if it really did get opened and I just don’t know it, but I checked my REQ collection and saw nothing new.
I had the same thing happen with a silver pack. It gave me a message saying something like “Your pack was purchased but there was a problem. You can find your Pack in the Unopened Reqs menu.” So I find a silver pack in my unopened Reqs, but when I try to open it it tells me “Pack already opened.” After I played a game it was gone altogether, and I have no idea if I got anything out of it.
Generally when issues like this happen, the items do still get added to your inventory you just skip the opening animation. You can either hard reset your console or check your REQ items here on Waypoint to find the new items 