Multicurrency in Drupal Commerce

Hello. I have integrated the Multicurrency module for commerce on the site. Everything is working great. However, the shipping cost and order total are calculated not in the current currency but in the default currency set in the system. I have two currencies, dollars and euros, with the dollar set as the default, but sometimes I need to calculate in euros, and that isn't happening. Maybe I need to create a rule or condition? But what kind...