Have you called the store you bought it from? Also, JUKI HAS A 5 YEAR WARRANTY.
I have found most online stores will back their sales and provide trouble shooting over the phone, even if you are past the 60 days.
This was a new machine, not refurbished, right?
what type of thread, needle and fabric are you using?
when did you oil your machine last?
there is a Juki facebook group that maybe able to help as well.
best wishes.