My bad, i didn't know there was any compulsory rule that we must include username and date because i ONLY read from where the organizer made comments that the
contest is now open, does it mean my entry will be disqualified just because i didn't include my username and date

Was actually thinking that the attaching username is just at will never knew it was mandatory. Hope it doesn't get disqualified because i really spent money to gather the stuffs i used in baking this pizza. My first time participating in a pizza contest though, will do better next time.
Next time, a new thread should be opened for contest like this and not merged with the previous contest so that some mistakes can be avoided.
You should have read the rules more carefully mate. It takes a lot of time and efforts to make a pizza, I'm sure it was hard for you since it was your first time. You spent so much but didn't have the time to read, that's really unfortunate.
As for qualifying, I believe you don't. I know it seems sad, but rules are rule. The rules clearly states username + date and I don't think icopress would allow any exceptions.
The only solution I see is that you have to remake everything from the scratch and re submit everything before
9th June.
Fair enough then, even if it is disqualified, the most important thing is that i enjoyed the pizza i made myself for the first time, it was yummy
However, i still stand that new thread should be opened for contests regardless that it's an annual event but it makes it look more organized. If they care so much about the previous contest what they should have done is to open a new thread and caption it ''links of past pizza day contests'' and write the links on that thread, it's as simple as that.