What is the ruling on accepting an increase in shipping costs - which was not known beforehand - upon receiving the goods from the shipper, especially when purchasing electronically from China, and does this fall under the general affliction (umoom al-balwa)?

Ignorance regarding the quantity of the shipment is excused because its ultimate outcome is knowledge, it does not lead to dispute, and it does not prevent delivery and receipt. This is similar to selling a pile of goods (ṣubra) or similar items in bulk (juzāfan) by parts, such as selling a garment, a pile of goods, or a flock where each cubit, or qafīz (a measure of volume), or sheep is sold for a specific price. The sale is valid even if its quantity is unknown because the item being sold is known by observation, and the price can be ascertained by weighing, counting, or measuring. This is the view held by the Malikis, Shafi'is, Hanbalis, and some Hanafis.