Fix issues on wordpress

My website www.risingview.co.uk has been hacked.

For example - http://www.risingview.co.uk/client-360/Centro-House-Stirling.html

All the aerial 360 pages that seem to be in the /client-360 seem to have been affected with the same issue. I cant see any of the normal www.risingview.co.uk website being affected.

From looking at the ftp the html files have not been modified but the folders that are associated with them all seem to have been modified on 31st May 2019 at 22:21.

I have went to the people who host my website to just roll back the ftp a month but they say the hack has been there since January 2018 and to just start fresh and get a new website.

This is not an option as we have spent a lot of time and effort on this website and I am sure it can be sorted.

What I want them to do is roll back the site at least 1 month before the issues, then make sure all the site and plugins updated etc

Can you help with this please?