Bed leveling UBL delta printer

[Roxy]

Also... you should first verify you can print a small item at the center of your bed without any bed leveling active. Usually, when these types of difficulties show up trying to bring up a bed leveling system, it is because this can not be done.

If you can not print a small object at the center of the bed... It is not possible to bring up the bed leveling system.

You can just do a G29 D to turn off the UBL bed leveling system. But if you turn off the //#define AUTO_BED_LEVELING_UBL option, that would be best. With the bed leveling code not built into the firmware, there won't be any confusion if it is responsible for any issues you see trying to print a small object.