DTG K3 printing problem

You need to attach the image mate ;-)

attached image
thanks in advance

How is it supposed to look like? Attach the graphic as well.

Hey there ,just read this forum post it may help you ......
Club.myce.com/f7/black-lines-paper-when-printing-108673/

also check it might need a new wiper rubber,if worn then a small layer of film will contaminate the head causing this kind of problem

usually the problem arises if the encoder strip is dirty or the encoder belt & wheel is dirty. clean the encoder strip with windex, make sure there are no scratches on it. and check if there is dusk particles on the belt and wheel and clean both parts. also, you might check if the carriage can travel freely. you might also want to oil the rails with gun oil.

I'd say You platen's bottom may be uneven. Does it print fine until it stops and then prints in one place?
Flatten platen's bottom or adjust media switch.