Minimum Purchase Error

Product:Quantity:Price:Total:FE-9x6, Cummins, size - 9″ Diameter x 6" Tall cylinder shaped1  (Error)$12.00$12.00FE-KTA19 Cummins KTA19, Size, 13.3/4" diameter x 18.9/16" tall1  (Error)$18.50$18.50FE-MTU8v2000 MTU 8V200, Size - 19 1/4" Diameter x 15" Tall Strait Cylinder Shape1  (Error)$15.50$15.50FE- Volvo 122P, size - 12 1/4" Diameter x 10.5" tall cylinder1  (Error)$14.50$14.50FE-6BTA-5 Cummins 6BTA, size- 6"diameter x 10.25 Tall cylinder shape1  (Error)$13.00$13.00FE-Stork 18"D x 8"T Strait1  (Error)$16.00$16.00(FE-16V) Size, 10" diameter x 13" tall, cylinder shape1  (Error)$14.00$14.00FE-Stork. Stork Wartsila WerkspoorDiesel, Size, 18" Diameter x 8" Tall Strail Cylinder Shaped1  (Error)$18.00$18.00Error => Minimum Purchase quantity of 6 units required of each product within the product group. (Rule ID = 541)