I've had better results flushing the transmissions , sometimes called a fluid exchange, instead of just changing the filter and topping of the fluid.The problem with just changing a filter is while you clean debre from the pan and install a new filter, you still have the majority of the old,contaminated fluid in the system. The flush/exchange process involves a cleaner and a conditioner plus all new fluid in the transmission is replaced. I have had good results with BG products.
Good luck