The circuit I use, which is on Google, provides a soft stop. In fact, you can get a coasting stop. I can't understand why you are having this problem. Maybe you wired it all wrong. Recheck your wiring again, and again. When you are absolutely sure it is wired right, how about posting the circuit and control program.
It seems quite odd to me that you are a having a problem with a perfectly simple problem, one that thousands have solved, but you can't see the need to tell us what you have done.
John
PS: You should also tell us whether your motor is brushed, series or shunt wound, or brushless.