Hi oludayo,
Based on your description of how you studied for the GMAT for both attempts, it’s possible that you started practicing random practice questions prior to fully learning each GMAT topic and thus were unable to make significant improvements to your GMAT score. If you need a higher GMAT score to gain acceptance to your desired programs, you might consider re-adjusting your study routine prior to a third GMAT attempt. When studying for a retake, strive for linear and targeted learning and follow that with focused practice. In other words, you want to master one topic before you move to the next.
For example, if you are learning about Number Properties, you should learn everything possible about that topic: LCM, GCF, units digit patterns, divisibility, remainders, etc. After that, be sure that you practice with a lot of questions (50 or more) just on Number Properties. The results of that practice will help you to determine how well you have truly mastered that topic. You will want to follow this study routine for verbal (sentence correction, critical reasoning, and reading comprehension).
To allows for such focused learning and practice, you may consider using a self-study course rather than a book. In comparison to GMAT prep books, self-study courses typically provide detailed study plans and have granular analytics, so you can easily track your progress as you move through the course. By being able to track your progress, you will remain more engaged, and you’ll be able to forecast when you are ready to take your real GMAT.
If you are finding it difficult to find time to study for the GMAT with your busy work schedule, I welcome you to read an article that I wrote that provides some advice of
how to find time to study when working a demanding job.
Feel free to reach back out with any additional questions. Good luck!