Query parameter ignoring first value in excel reports in ALM

I have a query where i am trying to pass testers id through parameter.

Select * 

from BUG

where detected_by in @parameter@

and in parameter, i am entering    p7777','p1234','p3456','p2340

but when i am executing the query its running successfully without any problems but somehow first value is not being considered. i tried to enter a dummy value as the first value and then my values something like this

p00','p7777','p1234','p3456','p234

but even then its not considering 'p7777'. i tried to rearrange the order but even then igonres the first value.

tried to google it but couldn't find any solution. please help.