Try does not solve like Run

I would like to give some feedback about ...

From: https://checkio.org/mission/most-wanted-letter/solve/

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When i check my solution with the try it function, for example the String "One" the result is always right, giving an e as wanted in the solution. But when i Run&Check it the solution is always 'O' or 'n' what is given as wrong. So there seems to be some different behaviour between these to functions.