Lab 2a

I completed steps 1-52 yesterday on Sim 2A and then continued from 52 today, but somehow I switched up the instruction manuals and all the work that I did today 52-90 was from sim 1B. This was a stupid mistake on my part but I am now in a predicament where I don't know how to undo , or what to do about the work I just completed. If I can just get lab 2a reset so i can restart from the beginning of 2a that would be great. Thanks