The purity of Werner state in non-extensive formalism associated with two different constraints has been calculated in a previous paper by Bagci et al.(17) Two different results have been obtained corresponding to ordinary probability and escort probability. The former has been shown to result in negative values thereby leading authors to deduce the advantage of escort probabilities over ordinary probabilities. However, these results have only been for a limited interval of q values which lie between 0 and 1. In this paper, we solve the same problem for all values of non-extensive index q by using a perturbative approach and show that the simultaneous use of both types of constraint is necessary in order to obtain the solution for a whole spectrum of non-extensive index. In this sense, the existence of these different constraints in non-extensive formalism must not be seen as a deficiency in the formalism but rather must be welcomed as a means of providing solution for all values of parameter q.