i'm currently working on currency misalignment , i have 3 variables the productivity differential and the NFA, as independent variables and REER as dependent variable, but my REER is unfortunately stationary I(0) the other are I(1), how can i run a cointegration or find a long run. By the way i used a DOLS despite having a I(0), and the misalignment results was following the literature for some countries and not following for the others, i'm working on 32 countries