If you have a normal recovery (ie. not a straight arm recovery), I think you’ll find that if you enter the water further in front of you (in line with your shoulders but in front of your head a little bit), it should be more difficult for you to enter palm out (you can try this sitting in front of your computer).
Beyond analyzing what’s wrong with your stroke and causing the problem (which is very hard without seeing it), an obvious corrective drill, as mentioned above, is finger tip drag. When dragging your finger tips the back of your hand should face forward and your fingertips should point down. Hold this position throughout the stroke (fingertips down, back of the hand facing where you want to swim).
Would write in more detail but I’m running late for a meeting. Good luck over the weekend.