What you did you cannot change so don't waste your time focus on SFM Paper. The most valuable time is going on so just relax and in next paper write the answer with Black Pen All the best 👍👍
First ,we must understand, when a particular thing is emphasized by the Institute and it means is mandatory like amendment otherwise we could have taken it easy, and you yourself know internally that writing in Blue pen is wrong. Hope Instituite would not punish severely, howver please communicate to the Institute, Since, how much pain you took to write this exam aftre 6 months.