Good that it worked for you in Costa Rica. There were some SMS issues with my card too. I reported to yackie and they refunded me the couple of sms I sent. I think the issue is still there, but not a major issue for me, because I just use my cingular sim for sms whenever I travel. I have to carry 2 phones, but that's fine.
My voicemail problem mentioned above has not been resolved though.
I am assuming you are sending sms to the +354 number right? Alaos, why can't you access your account, password lockout, error? yackie should be able to reset that I think. You know there are 2 ways to access the account. via
http://www.yackiemobile.com/content/home, and
https://my.yackiemobile.com/
Phones: Xiaomi Mi Mix 2, Samsung Galaxy A50, ASUS zenfone 3,
Sim cards: AT&T (Contract), 3 UK, Piranha Mobile