Dear Patryk,
I just noticed in admin side that in the vendor dashboard and order listing page of Vendors, order total shows the total amount of that particular.
If a customer ordered 2 different products from two different sellers, why should the seller1 see the total order amount. Instead he should be viewing only the sum of his item in that particular order. The seller can get confused seeing an higher order amount comparing to the order he revived. Am I correct?