By all means give the SAT and/or ACT another shot. But also recognize that not everyone ends up with the score they hope for. There is also no magic formula as to how to study (if there was someone would bottle and sell it).
If your scores stay in the same range then you may need to re-evaluate your college application list and make sure it makes sense given your actual scores. If you feel your scores don’t reflect your ability and don’t match your transcript then consider some test-optional colleges. Here is the test optional list sorted by state. https://www.fairtest.org/university/optional/state