Use column in a variable Table

hello guys,

i have a problem that is soooo frustrating to me,

whenever i copy a DAX code that uses a variable table, then reference a column of this variable table inside another variable it works so fine for them, but when i tried to use the same syntax, it just doesn't work for me ?!!!!!!!

Driving me crazy !!!!!!!!

what is wrong here ?!!!

VAR SourceTable = ADDCOLUMNS ( ALL ( Sales[ItemCode] ), "@Amt", [Sum of Net Sales Value] ) 
VAR Result = RANK ( DENSE, SourceTable, ORDERBY ([@Amt], DESC) )  
VAR _Table = ADDCOLUMNS ( ALL ( Sales[ItemCode] ), "@tank", RANKX ( ALL ( Sales[ItemCode] ), [Sum of Net Sales Value],, DESC, DENSE))  
VAR _DisCount = DISTINCTCOUNT(_Table'[2tank])  
RETURN Result & " OF TOTAL " &_DisCount