From 690-720 in Mocks to a 590 in Actual Exam

This is my first GMATClub post where I'm actually starting a discussion. Usually, I'm just reading what people have written but this time I think I need some expert guidance.

Here's a little back story, I started my GMAT Prep last year when I underestimated the exam severely and at the same time overestimated myself as well and scored an understandable 530 (Q38/V27). Realising that its complexity is due to the adaptive questions and various proprietary algorithms, I planned to start my preparations again. But due to many personal family issues and losing an important family member to covid, I couldn't start right away. So, I started back in May 2022.

Here's how I tried to do things differently, I took coaching to clear up my basics in both Quant and Verbal and then I started hitting the question banks. Once I was sure about it, I started giving full-length mock tests because these were missing in my 1st attempt. I gave a total of 8 mocks (2 free Official GMATPrep Mocks and 6 MGMAT) and when my score was consistently going above 690 in each one of them I was pretty confident to see at least 100-120 points improvement from my 1st attempt. But to my utter surprise, I scored a disgraceful 590 (Q40/V30). When I clicked that submit button after I was done with the AWA and this screen which should've shown 680+ was flashing a number with '5' in the hundredth place I froze for 2min. Instantly, the whole timeline I devised in my head for my applications was destroyed because this was indeed the first step, getting a GMAT score.

Now after feeling lost for almost 24hrs I'm trying to pull myself back and think about what went wrong. From what I could feel while giving the exam:-
1. My accuracy in SC remains very inconsistent (and that was reflected in the mocks as well).
2. My obsession with a 700+ score was so bad that my entire prep was focused on doing the 700+ questions right which I didn't even get because I'm pretty sure I got a lot of 600-650 level questions wrong.
3. Assuming that if I'm able to do 700+ level questions, then 600-level questions will be easy for me to do was a pretty bad and fatal mistake. 600-level questions are like that cute kitten where it looks like you can go n pet her but scratches the hell out of you if you did it the wrong way.

So only 24hrs after losing all hopes I'm back at it again, willing to give my best again and make it happen. But I will need some guidance from you guys and want to know what the experts here have to say about my situation. The materials I have in hand are:-
1. GMAT OG 2022
2. Manhattan ALL THE GMAT books
3. 1-month left in the Magoosh subscription
4. My own experience

Please help!