Can you check the dates and see if the replays are from the same patch? Note that our system can't open replays from previous patch cycles.
Also, I am a bit confused about why you lost matches due to the replay issues you're experiencing. Are you trying to open replays while you are actively playing the game?
Okay next question, do you have any mods installed? To answer your question I just tried opening my last game replay, and it worked just fine on my end. Also, make sure that you have the client completely closed out before opening the replays.
Also, I think I may have misunderstood you when you said you lost the match, you lost it as in it went missing, not as in getting a defeat in a battle right? O_o
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