Facebook for Woocommerce Sales price issue

We are using Facebook for Woocommerce to sync our products from Woocommerce to Facebook and Instagram.

We haven’t set any sale price on any of the products, there are only regular prices.
Although on our Instagram shop we see that sale prices are set with the same value as the original price. (Like “310,00 € 310 €“) I’ve turned debugging on and as far as I can see there is no sale price value submitted. We are using wpml, but have no multi currency setup, our only currency is euro.

If this is more likely a wpml error please let me know to get in touch with them.

Regards,
Richard