Levis Signature Jeans — waist size

i have purchased two levis signature jeans with waist size marked 36 inches of which one jeans waist was in true 36 inches but the other jeans waist was found to be 34 inches inspite the jeans tag showed 36 inches.i only wear signature jeans soi did not try it at the show room. when complined to show room at guwahati they refused to replace it
IN FUTURE PLEASE CORRECTLY CHECK THE WAIST SIZE.

SUBHASHISH GUHA