"Don't use force" is "Don't use direct force"!
In taijiquan, there is a phrase that causes a lot of confusion. It is "Don't use force".
What this really says is that in taijiquan movements, we do not use direct power, instead, we use indirect power. Or in other words, the point of contact cannot issue power. Power comes from another place that reaches the point of contact. This means the point of contact only has passive power.