Can you please be a bit more specific.
What computer os re you using.
What printer software. what slicer .
How are you transferring the file
What 3d printer software are you using.
It sounds like you may be trying to load an stl or other 3d graphic file directly onto the sd card.
Cad files are used to generate the design or one can download from the internet.
A control program lives in your printer or computer
the stl file is then sliced with
Slic3r
Cura
Simplify 3d
Other slicer
It is converted to g code
inyour case an .xyz file
it is then run on the printers firmware.
Maybe you can start with brief history of yourself and the printer then give us the full story of what you are doing.
I do not own an xyz printer an likely never will but will help the best i can.
Soliddoodle 4 stock w glass bed------Folger Tech Prusa 2020 upgraded to and titan /aero extruder mirror bed
FT5 with titan/ E3D Aero------MP mini select w glass bed
MP Utimate maker pro-W bondtech extruder
Marlin/Repetier Host/ Slic3r and Cura