I solved it. the problem is the power cord., before it was connected to power outlet together with Imac, Printer, electric fan & cutter. i plug the power to a main outlet and it was running continuosly till it finish. Now i am cutting even if i make many ups. i have a job for 21 tshirt front & back, gold sticker. ever since i change the outlet its not stopping i am about halfway with my job happy that cutter is working fine . Thank you all guys for your help and suggestions.