Fix - Bigcommerce Website Indexing from Japanese Website (Hacked)

Hello, I have a Bigcommerce website and it was somehow hacked I think. The website is indexing from Japanese links. Please see screenshots attached. I contacted the Bigcommerce support and this is what they said: "In this case, we can see a few of these translated links lead to the contact us page. We may want to add the SEO values for the page here: [login to view URL]" "To see if you can replace any seo values currently associated with the url. In this case, we may want to go ahead and submit your sitemap to Google using the steps here: [login to view URL] after updating your SEO values. That should take care of it for us here. We'll need to give the contact us page new values, then tell google where they can find those new values with the site map" Only If you can fix this apply. I need someone with experience in Bigcommerce and SEO and knows how to fix this!