What am I doing wrong?

[unclebill]

Here are photos of the last 2 items I tried to print. As you will see the same thing has happened to both. The top of each has somehow shifted.
I've never uploaded picture before I hope this works.

[William]

Hi，there are several reasons:
Reasons: 1. The printing speed is too fast. 2. Printing produces piles that hinder the operation of the nozzle. 3. The resistance of the xy axis is too large 4. The motor is overheated (above 60 degrees). 5. The acceleration is too large. The 6.xy axis timing belt is too loose, slipping and jumping teeth appear

Treatment: 1. Reduce the printing speed and control within a reasonable range. 2. Appropriately reduce the print head temperature (adjustment at 5 ° C). 3. Lubricate the XY shaft (lubricating oil, rail oil, or engine oil). 4. Reduce the current of the motor 5. Reduce the acceleration of the motor (the factory setting is generally no problem, adjusted in the screen). 6. Tension the synchronous belt (jumping occurs when it cannot run).
Hope to help you.