Problem with date indicator

Hello dear friends!
I ve just became a happy member of your comunity.
My uncle gave me as a gift his watch IWC Schaffhausen automatic and there is a problem with date indicator. I think it doesn 't work.
Yesterday i put the date (10), i ve just looked at it, the date is the same.
What's happened with them? Maybe i do something wrong?
Sorry for my bad english)
Thanks

Welcome to the forum. Simple mistake to make I suspect, wind the watch on 12 hours.

After fully winding the watch, pull the crown completely out and advance the hour hand through a 24 hours cycle. If the day / date indicator does not advance, your watch may need a trip to the IWC watchmakers. Do not advance the day / date with the quick set position, crown in the second position, between 20:00 and 02:00. The gears are engaged during these hours and you may damage them.