If you filed and it was Accepted you can not add another one. So you need to delete the second W2 and put your return back to the way it was when you first filed it. Then you will need to do an Amended return to add more info.
To amend you first need to wait for the IRS to be done processing your first return and you get the first refund. Then you can amend. The amended return won't be ready to fill out until late February.