What does this really mean ?

Since it was my first submission for problem A (Packets) in Manthan, Codefest 18 (rated, Div. 1 + Div. 2)

I got solutions to the first 4 problems, but could not submit even one today. Probably my bad luck.

Is there any issue with the System on the CodeForces side ? Did anyone get any similar issue, where you could not submit due to similar problem ( Error being popped up after submission as a notification window at the below right corner of the screen saying ), "You have submitted exactly the same code before"