Allies Mission 9A - transport helo bug

Product: Command & Conquer Remastered
Platform:Steam-PC
Summarize your bug game bug, cannot finish mission
How often does the bug occur? Every time (100%)
Steps: How can we find the bug ourselves? Red Alert, Allies 9A
What happens when the bug occurs? Mission cannot be finished if the transport helo for Kosygin is diretected to another landing destination.
What do you expect to see? Mission accomplished

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After bringing Kosygin to my base, a transport chopper comes. If you direct it to another destination than it would land by itself, the mission cannot be accomplished anymorge. Allthough Kosygin goes to the chopper, flies away, and it says Kosygin rescued, the mission goes further. 
I had to load a savegame, didn't touch the helo this time, and tada: Mission accomplished.