Given your performance on the actual GMAT, it appears that you still have some relatively weak areas in problem solving in quant. Somehow you still scored in the mid top upper 40s on your practice tests, but still, clearly, if you scored 37 in Problem Solving on the real test, you have some weaker areas to address.
I'm guessing that you basically know which areas of quant are your weaker areas. If you don't you can analyze your practice tests, review your ESR, and, possibly most importantly, consider which types of quant questions you'd rather not see when you take the GMAT.
Once you have identified those weaker areas, you can strengthen them one by one, by first making sure you fully understand them conceptually and, then, doing dozens of practice questions involving each topic.
For more on locking in an upper 40s quant score, you could read this post on
How To Increase Your GMAT Quant ScoreRegarding verbal, many people score lower on verbal on the actual GMAT than they have when they practiced.
One reason for this pattern is that many verbal practice questions are based on the GMAT Prep test verbal questions. So, when people take the GMAT Prep tests, they have already sort of previewed the GMAT Prep verbal questions.
Another reason for this pattern is that the verbal questions on the actual GMAT have evolved, and so, they are a bit different from what people are used to.
Overall, to score higher in verbal on the actual test, you need to become super good at seeing what's going on in questions by analyzing every choice of many verbal questions to develop skill in defining why incorrect choices are incorrect and correct answers are correct.