I have a thor double needle 18" arm the inside needle is shedding and breaking the thread . The outside needle is doing great. I did put new needles on but did not help. Its got to be an adjustment I need help with I am new with all of this

I have a REX 345-3L I jeed serviced. The thread is breaking and gathering around the bobbin.

Check your tension and make sure you haven't got a bad spool of thread.

Are you sure it's the needle snts not the bobbin? I'm not 100% on that but it's my go-to method. Then I check all the tension areas... how this helps