All texts not translated when using WPML with Appointments+

Hi, i have a Wordpress site that use WPML for translations. When showing appointment details then the texts "Service name:", "Date and time:", "Lasts (approx):", "Price:" are not translated according to the selected language (translation files in folder appointments\languages). Instead, the texts for these labels are always according to the "Default admin language" setting in WPML settings. How should I do so all texts used by Appointments+ plugin are according to the translation files. Thanks, Johan