Are you pressing the bottom arrow button to bring up "EDGE" first before hitting enter. Not ROLL or PIECE.
Also, what program are you using, my program allows for roll feed at the start /finish. Mine will also feed the full length of what it's going to cut first, so if I cut something 6ft it will prefeed that 6ft... but I have that turned off.
Try a design thats only 1 square ft, it should only peel off a foot of vinyl, if it keeps going there must be something in your program.
You can reset the Roland to Factory Default by scrolling thru the options.
I found the factory default but cannot select it. Do you press enter?
As Techsign33 said, you may have sent a long cut file and it's still sitting there waiting to cut...cancel all.
Try a test cut from the GX itself (scroll thru menu and hit enter......don't send a test from the computer....if it works ok then you have a problem in your setup in your software.
What program are using to design/cut from.
Is it the same file that it happens on, if so try a different one. Was the file made by you or sent to you, if sent to you check that there isn't something way off to the side somewhere.
You haven't added another printer lately, if so, make the GX the default printer.