I have all but 2 technologies unlocked and have 3 abandon tablets left to get the remaining unlocks. The frustrating part is that when I use a tablet it just says access granted with no options to unlock one of the final techs. Fortunately it does not use the tablet so I am able to try multiple times until i get it.
I would expect that this should not happen and when I use the tablet it would show me the remaining 2 and I could pick one.
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