Thanks for writing.
But the viability of the baby is not confirmed which occurs when heart starts beating. This is what your report means by "fetal cardiac activity not imaged"
cardiac = heart
activity = beating (living)
Usually working heart is seen around 7 weeks. In some cases it appears late especially if you have wrong dates.
So you have been asked to repeat ultrasound
after 2 weeks so as to confirm if baby's heart has started working or not. If by next ultrasound also your baby's heart does not start working then it indicates it is non viable pregnancy and has to be aborted or will abort on itself.
I hope I have made it clear to you.
All the best.