Microformats.org errors on the missing fields author and updated

I use the Sydney Free theme.
By looking at the structured data from webmaster tools, I have noticed many microformats.org errors on the missing fields author and updated.
It would seem that this comes from the theme.
What do you think ?
My website is http://reliure-dorure-quersin.fr
Thank you for your reply.

Hello @ecoprest,

Please check these topics:

Please feel free to ask any other questions that you might have.

Kind Regards, Roman.

Hello and thank you for your very quick reply. I will read these topics.

You are welcome @ecoprest,

Kind Regards, Roman.