listings alone can't be use you need sales

there is a sale on mp was made in the past 3 months

at 6.20 usd

keys that day 1.68 usd

6/2/1.68 = 3.69 keys

2 sellers on backpack below 3.7 keys so it cant be used

here are a few history's with movement in the past 3 months that you would need to look into to see if there is any usable sales

https://backpack.tf/item/12244095557

https://backpack.tf/item/3805193659

https://backpack.tf/item/2814350431

https://backpack.tf/item/2775532608

https://backpack.tf/item/2741402012

here's something to help you further

https://forums.backpack.tf/topic/79020-guide-how-to-make-an-unusual-price-suggestion-2021-edition/

https://backpack.tf/rules