Hi Dale2012,
Thank you for reaching out to us in our community and welcome, sorry to hear you aren't able to access your Voicemail while in Turkey due to the pin showing as invalid, I will be more than happy to reset this for you, not sure why this has happened if this is the pin you have used previously, I will send you an invite into a private chat, once received please click on the purple envelope to accept.
Regards
Paul.