it is asking me for a serial number that i do not have it
Have you tried uninstalling Lightroom?
Then re-installing Lightroom from the Cloud?
Have you tried http://helpx.adobe.com/creative-cloud/kb/ccm-prompt-serial-number.html
Welcome to the Adobe Forums,
The order that you purchased in March 2014 is of Photography CC, if the Light room is asking for serial number, do refer to :
I hope this will resolve the issue.
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