I keep getting “error starting the match, try a few minutes later” with one specific deck. Every time I restart the game, the Mage deck is shown 39/40 although I have completed it many times. It keeps showing one card that I do own invisible/transparent. Haven’t used the deck in 4 months, made it 40 cards a few days ago; haven’t played with it yet!!
i also get the same msg.
and not only for decks that suppose to miss out some card, although it dosen’t
If this happens specifically with Death Knight cards, then you might be able to fix this by deleting the deck (after taking a screenshot) and then rebuilding it - not with a code but manually (hence the screenshot).
Many people currently have these issues; this seems to be caused by Blizzard fixing an earlier bug where people received golden versions of cards before they had actually earned them. Those not-yet-earned golden versions have now been removed from your collection, and might invalidate decks.