Restore Help Please :(

Hi all,
i have just wanted to restore my iphone 7, i have downloaded the IOS 10.3.2 from trusted site.
i have made backup and all is okay,
then when i restore my iphone using the downloaded version, at the end of restoring my iphone stuck on connect to itunes ! i have connected and it shows a message says : there's a problem with iphone which needed to be updated or restored !!
i tried to use update with the same ios version and it says iphone have been updated successfully but it still stuck on connect to iTunes ?
whats wrong ? and what to do now please !