.... but what i get is 00-00-00 00:00:00.
This indicates that you are not writing to the database correctly. To fix that problem, use something similar to...

UPDATE guestlog SET date=NOW() where ID=...
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as Joost suggested.

To format the date for display, use DATE_FORMAT(col,format_str) in your SQL query

SELECT cola, colb, DATE_FORMAT(date,'%d, %H:%M') FROM guestlog ORDER B
+Y date DESC
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