Guys I need advise. I took the GMAT for the final time and got 70 points less than what has been officially reported to the school in my R2 application. I went from a 620 to a 550!!

I have no clue what went wrong I was shocked when I saw the score on the screen. Last month I told admissions I was going to take it again after the R2 deadline but before they send out notifications on March 1st.. They said they would hold the final review of my application until then. Now I'm not sure what to do. I have already interviewed and it went really well.
Do I self report like I was planning on doing, just tell them it was a lower score and to review based on what they have currently, or tell them something else? I am even thinking about giving the excuse that I was sick with a mild flu but still wanted to give it a shot since I could get a refund or change the test date
The official report will make it to their office in about 2 weeks so they will find out eventually. I feel like my smartest move would be to ask them to move forward since the latest score doesn't help me while being vague on the actual score, hoping they make a decision based on what they have currently.
Clearly I need help...