is this a Kossel style delta, ie with 2020 aluminium extrusion uprights and rollers along the extrusion
If so so a few moves from xyz=0 to xy=0 z=max and back again and watch the nozzle does it appear to snake side to side as it moves?
also take a look at the carraiges as they move up and down do they all track straight or do they have a wobble?
Finally look at all your rollers, do these ALL track straight?
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