Hi, I would like to report a bug .
I get negative value of function unix_timestamp.

I want to get a duration of format HH:mm:ss

     unix_timestamp(duration,'HH:mm:ss')

When I test it backwards ,it works , I get my duration in a well format
with correct values. This:

     from_unixtime( unix_timestamp(duration,'HH:mm:ss'))

But anyway , I can not get unixtimestamp in seconds.

Thanks