How to avoid this endplay?

This hand I played in a BBO-team-match. And I misdefended.
Click on my nick to show only my hand and dummy's.
Right-click the diagram and choose "hide played cards".

Click on "next" for every trick to see how the play went.



Do you see where I made the mistake?

After winning the diamond J it was mandatory to cash diamond A. THough partners lenght signals in the minors were wrong, I should know that declarer's distribution is 4423 and partner holds both minor Ks.