Bendy and the Ink Machine: Go to account details, licenses and product key activations. There, the product key should show according to the date it was activated. My guess is, it will show it as complementary on the right, as mine did. I believe the problem was created when the complete edition was made, replacing all previous editions. If you remove the license from your account, it will no longer be tagged as in your library (even though it doesn't show up in your library) and the game can then be purchased. (It's in a humble bundle right now FYI)

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