Printer will start printing properly but then at approximately 1/2 inch in height the printer gets stuck on a layer and does not continue to move up but keeps printing continuously at that level while counting up layers. I have printed models lower in height and they work fine, but seems anything higher than that gets stuck. I have checked the belt under the unit and it is intact, I can move up and down when powered off and don’t feel any obstruction, also will move by pressing button after I have homed the unit and I don’t see any debris interfering.