Opencart Developer Immediate hack help needed

I need an experienced full-stack developer with opencart CMS experience to fix a hack. Version 3.0.3.3. Clients are experiencing a RAT redirect. Need immediate help to resolve this issue. I will be retiring this opencart store in the next couple months and changing cart platforms. No new apps or major changes have been made. SIte is continuously backed up but I am unsure of when the last clean backup would be from. No suspicious behavior on the admin side.