Pages not found

yesterday after an update of sydney pro  from menu of my website www.mcell5g.it  disappeaed all linked page " page not found" on all menu ad i dont know how to solve ,, please help !!!

Have you updated anything else beside the theme? First try going to Settings > Permalinks and click on Save without making changes. Then if you can please remove the maint. mode so I can see your site.

Thanks! now maint removed to control i have seen in permalinks but no voice about save without making changes .
www.mcell5g.it

Found !!! OHHH yes solved changing permalinks as you suggested THANK YOU SO MUCH !!