How does one reset just part of a course instead of the whole thing?

so theres a part of the python course that deleted all my code and it even says “under your existing code” so it wasent suppose to happen. just want to redo that part of the course so ik my code is right cause how it is now i could put in anything and itl say its right cause i already passed that part

the same problem is happening to me. i think it may just be a glitch