How to cancel added product to cart if previous order has same commerce-product creator id I need this rule on before add product to cart react event, not after save commerce order. 

I need when user (buyer) klick second button add to cart (for multi order), system check the product creator id first, if the product creator id for the second order clicked is same with previous (where is actually on cart) system cancel the previous clicked order.

With this scenario I want to limit order only from same product creator for one times order. So if buyer want to continue order from different product creator they have to do after first order completed.

Any suggest how to solve this using rule??
tl;dr - Rules is really the place to handle this. You need to hook into the add to cart form's validate/submit handlers and take care of it in there.

The best way to handle this is to look into the answer provided here: How do I prevent a product from being added to the cart?

This answer was originally written to do that very thing: to prevent a product from being added to an order if some criteria were met (and the context was a marketplace multi-cart as well).