Dumbbell Hamstring Curl- Any good substitutions for this?

starting a workout program and this exercise isnt possible to do. Reason being my dumbbells doesnt have a good grip for the curl.

Any suggestions?


here is the workout.
Exercise Sets Reps
1. Goblet Squat 4 8-10
2. Dumbbell Stiff Leg Deadlift 4 8-10
3. Dumbbell Plie Squat 3 8-12
4. Dumbbell Hamstring Curl 3 8-12
5. Standing Dumbbell Calf Raise 3 8-12
6. Plank 3 20 Secs