Firmware Upload Error 1/1

Hello,
I purchased a DIY laser engraver from a vendor called skillpro on Walmart.com.
Long story short, I got it working, uploaded the drivers, & firmware using T2 Laser by Zax. I attempted to connect it (laser engraver) to another computer and since I’m a rookie, I tried to upload the firmware again and simply received an error stating Firmware upload error.
After contacting T2 Laser for help, they said that I may have currupted my “cloned” Nano. I attempted to clear it and re-upload and it doesn’t work.
Can you please help!? I need it for Christmas.
Thank you in advanced.

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I am having the same problem, when I hit either X axis directions it moves in the Y axis direction only forward. When I try to update the firmware I get the "firmware upload error 1/1" any ideas what to do?

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