I don't know who told you it's slow. But they lied.
Trim off the runners leading to the areas you don't want it. Pull out the plants where you don't want them. RAOK or compost them. Leave the established plants where you want them. Repeat in three weeks.
Trim off the runners leading to the areas you don't want it. Pull out the plants where you don't want them. RAOK or compost them. Leave the established plants where you want them. Repeat in three weeks.