คือผมลองทำโดยผ่านทาง paypal มันก็ตัดเงินผมปกติ แต่มีเมล์มาแจ้งเตือนว่า
Dear Advertiser
This is a courtesy notice that we have added a credit card ending in to your account as your default card used to pay for all click charges. If you did not intend to add or change this card, or you have any issues related to this notice, please contact our Customer Solutions department at YAHOO-SM.
For more information regarding this alert, please log into your account at
https://login.marketingsolutions.yahoo.com/en_US 
and click the "View All" link in the Alerts panel. For additional help, please visit our Help Center at
http://help.yahoo.com/l/us/yahoo/ysm/sps .
Sincerely,
ผมต้อง add บัตรใช่ไหมครับ หรือว่าไม่ต้องก็ได้
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