Recurring purchase bug

The currency does not change when I creating a recurring purchase from the supplier.

You need to furnish more information about what you mean. A recurring purchase invoice will reflect the way the specific recurring transaction is set up under Settings. If the supplier is denominated in a currency, and is designated on the recurring purchase invoice form, the resulting purchase invoice will be in the supplier’s currency.

If you are expecting the price to change, it will not. The numerical values will remain as designated for any item on the invoice unless you edit them.