Lab 3a

Hey there,

I want to make sure if I can restart lab 3a from very beginning because I was working on it already and after step 53 it pop up with a message (see the screenshot), and when I tried to fix it, I could not and lose the track of steps.

So I decided to restart but I had already did up to 53 steps and I am not sure if it will right to start it again. Also when I tired to start it again, but this time it is showing me that same message from very beginning like from step 3 and I can even start it again. I am stuck sonewhere in between, neither I have track to continue from step 53 nor to start it again, Help me please. Also what to do with the message that pops up. I would be really grateful to you for your assistance!