To stop it from spinning you want to not put your foot as far forward put the ball of your foot in the center of the tail.

Ive seen people do this. Theres 2 things i think it could be. You rather do to many pop shuvs so u get used to not popping straighting and slidding/sweeping. To fix this id take it easy on the shuvs and practice ollies to keep them straight. Rather that or ur just filicking it to forward so towards your toes which makes it kinda do a varial. Try and fix these and once u fully commit to it you will be able to land them

I had the same problem for many frustrating months. The little trick I found was placing my back foot slightly towards the frontside of my board rather than in the middle, and idk if it compensated for the flick in the opposite direction or not but it straightened my board right out.

you should try to put your tows on the tail and then when u pop stay above the board, and when u flicked try toleanback so Ivan catch it

Think about popping straight down and up with your back foot

Try putting your back foot all the way back on your tail without having it off the board, and make sure the ball of your back foot is right on the middle of the tail.

I had the same problem it's probably because you are not popping the board

Make sure your foot is central on the tail when popping

Make the flick harder and catch the board as soon as its done flipping

Keep your shoulders centered over the board and when you do the trick try to keep them straight so the board stays straight