Make sure you're on your home world and not visiting another world (if visiting, double check the timer after you return). If it was a personal plot it would be in wards 19-24 and I assume you know the size of the plot you bid on. You could go house by house and check, it will take awhile, but you have 90 days to collect your funds.

≪Losing the Lottery≫

You will receive a 100% refund of the deposit paid at entry.

Regardless of lottery results, any and all refunds for a given lottery period expire 90 days (Earth time) after the results period ends. Please be sure to accept your refund within this allotted time by accessing the same placard by which you entered the lottery.
Failure to accept your refund within the allotted time will result in the loss of said refund.

* You may only confirm lottery results and accept refunds while in your Home World.