Error session time finish

Error session time finish

Hello,

When a order is finished, I get this error:

"Error session time finish"

The error reporting set to "Development" shows no errors.

The order is created on the backend with the correct number, but the email sent to the costumer has no number and no date (i.e. 1/1/1970).

If I make 2 consecutive orders (in the same session), the order is created on the server, but the email of the 2nd order sent to the costumer has the 2 orders concatenated!

Please tell how to fix!

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