If your throw is decent and the yoyo starts to tilt after a few seconds, my guess is that it’s due to two factors.
- slowing down (less momentum)
- string twist/tension
If you’ve ever performed or looked up the trick gyroscopic flop, you can see how string tension/twist can cause the yoyo to tilt/flop.
Similarly, a string that’s been twisted string can cause the yoyo to tilt.
You may try twisting the string left or right to counter the tilting.
Or, you can let the yoyo hang at the end of the string until it’s done twisting, then wind the yoyo