There is a bug in this game:
playstrategy.org/9FPxYVEXB5t7

At move 31 I (White) wanted to play a7 to capture the big black group but the program thought the move was forbidden.

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Thanks @shinuito and @JLT for reporting these issues, and our apologies that you've run into these.
We can see two issues from this #17, #18, #21 are reporting the same bug, and #19 is reporting a second bug.

We will let you know when we have resolved these problems.

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@statmatt this should be another example of that second bug I think, if it's helpful for testing.

playstrategy.org/P9h0DQ7EwGw0

If you look from move 46 onwards, it's impossible to fill the last ko which should be legal for someone.

3

Thanks all for raising the bugs, we have just released a fix to the live system.
As usual, please let us know of any other bugs that you notice.

2

We realise that some users were having issues with correspondence go games and we are sorry for that experience. We have released a new fix which means you can now complete your correspondence go games! The go game will now end as soon as you accept an offer of dead stones.

As usual please let us know if you experience any issues/bugs and we will do our best to fix them!

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