In my opinion first we need to contact them thru team mail and personal email. we need to let them understan that what is SFI and how wr can be success. then we can reassign the downline, after assigning keep follow up by email. if neccessary provide other support like: gift certificate, TC.
weekly follow up and support how they need to do for another step. enxourage them to learn and use training method as much as they can.