Paragraph style changed to custom font on its own need to change it back

Site URL: https://www.slapyork.co.uk/info

I have a custom font for headings that I uploaded to the site and used CSS to assign it. This has been fine for months. 

Yesterday my paragraph style changed to the custom font on its own, I added no extra coding at all. I need it to change back to the standard roboto font but as I haven't coded this I don't know what to do! 

Any help appreciated! 

My inspector is reporting you are using the Roboto font family for paragraphs.