XPS 15 sometimes types - on it's own repetitively

XPS 15 sometimes types - on it's own repetitively non stop so i can't restart, open start menu to restart , or open a browser anything with a text writing area it would be writing ------------------------------ continuously .

called support updated bios and all pending stuff, it happened again just after

total now it happened 3 times and once the system couldn't shut down and i had to keep pressing on the power button to force shutdown and then to restart.

after hibernate (because that's what i set my power button to do, since i can't open start menu to press restart as a result of the constant --------- typing) it works fine 

This is a new system, i like and the support suggested replacing keyboard but i opted to replace the whole unit, i had this for 10 days but there was delay when receiving it so i don't want to the lose the option of replacing the whole system i have only 7 days, but i installed all programs that i wanted and i don't want to do this again....so if anyone experienced the same thing please let me know if it can be solved without replacing the system.