Some people have experienced problems when trying to pay their membership dues. When you press "Buy now" and get transferred to the PayPal system go ahead and press "continue" on the left above the card's logo. Do not go to the square on the right asking for your email and password.
Also note that PayPal unfortunately does not accept payments from all countries. In that case, please contact the treasurer, Dr Nina Lundholm for further instructions.
Best regards,
Karin Rengefors