Why is there 2% charge on top of your 1.8% or 3% on Shopify?

The 2% charge is a platform fee from Shopify if Shop Pay is not available in the region, or if you deliberately remove Shop Pay as a payment option on your store's checkout.

The 2% is applied to all third-party checkout apps. For lanes with Shop Pay, you may enable Shop Pay to remove the 2% platform fee from Shopify.