During the contest, I couldn't submit the solutions for problem A and B. Codeforces said that "You have submitted the same code before" even I haven't submitted any yet. That is confusing and I have also tried to fixed the code but it appeared to pop up the same message that my code is submitted before.

As you see, there is no submissions in "My submissions" and I don't appear in the ranking also. Then I used another account to submit solutions and it's fine :D.

I want to know what's wrong with this account !!