My License Needs Renewal As It Says Authentication Error

i have been using buildbox from 5 months now! and it always says authentication error after every 15 days or less. This time when i got this error as usual i tried to mail buildbox to give me key again! But its been more than 15 days and i have sent many mails but they are showing very non serious behavior that even not replying my mails? Did i spent this much money to get this stupid support? I am now very tired of this? Is there any online support they have other than mail? or what should i do?