There's a very good chance that you lost your true edge. It can happen gradually if you don't have some feather boards on the feed side. Before you know it you have a curve and are creating thick and thins on the strips.

If you have a good edge, flip it over and cut your board into two inch wide boards and then go back to cuttung strips from that. It will be easier to handle and won't twist on you as much.

If you lost your true edge on both sides, you would ride the board on a true straight piece of wood and trip a new straight edge. I once had it happen and just snapped a string line and made it straight again with a jack plane (long plane).

You can still scarf the strips you now have and salvage to good areas. Use a good feather board or two comming into the saw blade and a top feather board holding the board down to the blade (just before the blade. I personally don't like any feather boards after the blade or maybe a very loose one. Feather boards after the blade just causes binding and doesn't allow the wood to travel out easily. If my entire board has a twist or curve, I want the outside curve to be against the fence to avoid any binding.